LibreOffice

LibreOffice is a fully integrated suite of office applications developed as an open source project and freely distributed to all. It is the primary office suite for Fedora, accessible from the Applications overview. LibreOffice is the open source and freely available office suite derived originally from OpenOffice. LibreOffice is supported by the Document Foundation, which was established after Oracle’s acquisition of Sun, the main developer for OpenOffice. LibreOffice is now the primary open source office software for Linux. LibreOffice has replaced OpenOffice as the default office software for most Linux distributions.

LibreOffice is an integrated suite of applications. You can open the writer, spreadsheet, or presentation application directly from the Applications overview. The word processing, spreadsheet, and presentations applications are also accessible from the Launcher: Writer, Calc, and Impress. You can also open existing office documents (Open button) and manage document templates. Buttons at the bottom of the dialog let you download new features and templates and access the LibreOffice website.

The LibreOffice Writer word processor supports standard word processing features, such as cut-and-paste, spell checking, and text formatting, as well as paragraph styles (see Figure 5-1). Context menus let you format text easily. Wizards (Letter, Web Page, Fax, and Agenda) let you generate different kinds of documents quickly. You can embed objects within documents, such as using Draw to create figures that you can then drag and drop to the Writer document. LibreOffice Writer is compatible with earlier versions of Microsoft Word. It will read and convert Word 2003 and earlier documents to a LibreOffice Writer document, preserving most features, including contents, tables, and indexes. Writer documents also can be saved as Word documents.

LibreOffice provides access to many database files. File types supported include ODBC (Open Database Connectivity), JDBC (Java), MySQL, PostgreSQL, and MDB (Microsoft Access) database files. You can also create your own simple databases. Check the LibreOffice Features ➤ Base page at https://www.libreoffice.org/discover/base for detailed information on drivers and supported databases.

LibreOffice Calc is a professional-level spreadsheet. With LibreOffice Math (LibreOffice Formula), you can create formulas that you can embed in a text document. With the presentation manager (LibreOffice Impress), you can create images for presentations, such as circles, rectangles, and connecting elements like arrows, as well as vector-based illustrations. Impress supports advanced features, such as morphing objects, grouping objects, and defining gradients. Draw is a sophisticated drawing tool that includes 3D modeling tools (LibreOffice Drawing). You can create simple or complex images, including animation text aligned on curves. LibreOffice also includes a printer setup tool with which you can select printers, fonts, paper sizes, and page formats.

Also for use on GNOME is Scribus, the open source desktop publishing tool (see Figure 5-2) at www.scribus.net . Scribus provides professional-level page layout capabilities for all Linux distribution, with color management and PDF generation.

Calligra

Calligra is an integrated office suite for the K Desktop Environment (KDE), consisting of several office applications, including a word processor, a spreadsheet, and graphics applications (calligra package). Calligra is the new version of KOffice, integrating many of the older applications provided by KOffice. Calligra allows components from any one application to be used in another, allowing you to embed a spreadsheet from Calligra Sheets or diagrams from Karbon in a Calligra Words document. It also uses the open document format (ODF) for its files, providing cross-application standardization. There is also a Windows version available. You can obtain more information about Calligra from https://www.calligra.org .

Calligra Sheets is the spreadsheet application, and it incorporates the basic operations found in most spreadsheets, with formulas similar to those used in MS Excel. You can also embed charts, pictures, or formulas using Krita and Karbon. With Calligra Stage, you can create presentations consisting of text and graphics modeled using different fonts, orientations, and attributes, such as colors. Karbon is a vector-based graphics program, much like Adobe Illustrator and LibreOffice Draw. It supports the standard graphic operations, such as rotating, scaling, and aligning objects. Calligra Words can best be described as a desktop publisher, with many of the features found in publishing applications. Although it is a fully functional word processor, Calligra Words sets up text in frames that are placed on the page like objects. Frames, like objects in a drawing program, can be moved, resized, and reoriented. You can organize frames into a frame set, having text flow from one to the other.

GNOME Office Applications

AbiWord is an open source word processor that aims to be a complete cross-platform solution, running on Mac, UNIX, and Windows, as well as Linux. It is part of a set of desktop productivity applications being developed by the AbiSource project ( www.abisource.com ).

Gnumeric is a professional-level GNOME spreadsheet meant to replace commercial spreadsheets. Gnumeric supports standard desktop spreadsheet features, including auto filling and cell formatting, and an extensive number of formats. Gnumeric also supports plugins, making it possible to extend and customize its capabilities easily.

Dia is a drawing program designed to create diagrams, such as database, circuit object, flowchart, and network diagrams. You can create elements along with lines and arcs with different types of endpoints, such as arrows or diamonds. Data can be saved in XML format, making it transportable to other applications.

GnuCash ( www.gnucash.org ) is a personal finance application for managing accounts, stocks, and expenses.

Running Microsoft Office on Linux: Wine and CrossOver

One of the concerns that new Linux users have relates to the kind of access they will have to their Microsoft Office files, particularly Word files. The major Linux Office suites, including Calligra, LibreOffice, and Oracle OpenOffice, all read and manage Microsoft Office files.

Wine (Windows Compatibility Layer) allows you to run many Windows applications directly, using a supporting virtual windows API. See the Wine website for a list of supported applications; see also www.winehq.org , the AppDB tab. Well-written applications may run directly from Wine, like the Newsbin newsreader. Each user can install a version of Wine with its own simulated C partition on which Windows applications are installed. The simulated drive is installed as drive_c in the .wine directory. The .wine directory is a hidden directory. It is not normally displayed with the ls command or the GNOME file manager (View ➤ Show Hidden Files). You can also use any of your Linux directories for your Windows application data files instead of the simulated C drive. These are referenced by Windows applications as the z: drive.

It is possible to install Microsoft Office on Fedora using Wine. Although there may be difficulties with the latest Microsoft Office versions, earlier versions, such as 2002, should work fine for the most part (see www.winehq.org , AppDB tab, search on Word). Applications are rated platinum, gold, silver, bronze, and garbage. Although effective, Wine support is not as stable as CrossOver.

CrossOver Office is a commercial product that lets you install and run most Microsoft Office applications (it has a silver rating). CrossOver Office was developed by CodeWeavers, which also supports Windows web browser plugins as well as several popular Windows applications, such as Adobe Photoshop. CrossOver features both standard and professional versions, providing reliable application support. You can find out more about CrossOver Office at www.codeweavers.com .

CrossOver can be installed either for private multiuser mode or managed multiuser mode. In private multiuser mode, each user installs Windows software, such as full versions of Office. In managed multiuser mode, the Windows software is installed once, and all the users share it. Once the software is installed, you will see a Windows Applications menu on the main menu, from which you can start your installed Windows software. The applications will run within a Linux window, but they will appear just as if they were running in Windows.

With VMware, you can run Windows under Linux, allowing you to run Windows applications, including Microsoft Office, on your Linux system. For more information, check the VMware website at https://www.vmware.com .

Another option, for users with high-powered computers that support virtualization, is to install the Windows OS on a virtual machine, using the Boxes virtual machine manager. You could then install and run Windows on the virtual machine and install Microsoft Office on it.

GNOME Documents

You can use the GNOME Documents application to access and search for local and cloud-based documents. Documents can be text (word processing), spreadsheets, presentations, or PDF files. Currently, both Google docs and Microsoft SkyDrive documents are supported. You have to enable access from the Online Accounts dialog on GNOME Settings.

GNOME Documents is accessible from the Applications overview. The Documents dialog shows tabs for both Documents and Collections. Documents lists your local and cloud-based documents (see Figure 5-3). The Documents GNOME applications menu lets you view the documents in a grid (icons) or as a list. Collections are categories you can set up to organize your documents. There are buttons at the right of the title bar for searching, sorting, and editing. Click the Search button to open a search box with a menu that lets you search for source (local or cloud), type, and search target (title or author).

Click the checkmark button at the top right to open a taskbar, which lets you open the document or print it (see Figure 5-4). In the list view, click the check box to the left of the document you want to perform the task on. In the grid view, a check box is displayed at the lower right of each icon. When you click a check box, the taskbar is displayed with buttons to open the document in the appropriate application, print the document , and delete it. The Properties button displays information about the document. The Collections button lets you place the document in a collection. When you’re finished, click the Done button.

Document Viewers and Scanning (PostScript, PDF, and DVI)

Okular, Evince, and Xpdf are PDF viewers. They include many of the standard Adobe Reader features, such as zoom, two-page display, and full-screen mode. Alternatively, you can use Acrobat Reader from Adobe to display PDF files. You can install it with Packages once you have enabled the Adobe repository ( https://get.adobe.com/flashplayer/otherversions/ as Linux and (Yum)). The package name is flash-plugin.

All these viewers can also print documents . To generate PDF documents, you can use LibreOffice Writer or the Scribus desktop publisher ( https://www.scribus.net ), and to edit PDF documents, you can use pdfedit.

Linux also features a professional-level typesetting tool, called TeX, commonly used to compose complex mathematical formulas. TeX generates a DVI document that can be displayed by DVI viewers, several of which are available for Linux. DVI files generated by the TeX document application can be viewed by Evince, Okular, and LibreOffice.

To scan documents directly, you can use Simple Scan, which you can save as JPEG, PNG, or PDF files. For OCR tasks, you can use cuneiform. Yagf provides a desktop frontend for cuneiform, allowing you to scan and convert text. You can choose from several languages.

Ebook Readers: FBReader and Calibre

On Fedora, you can use the Linux versions of Calibre and FBReader for ebooks (see Table 5-6). FBReader is an open source reader that can read non-DRM ebooks, including Mobipocket, HTML, EPUB, text, and RTF (install the fbreader-gtk package). The toolbar holds operations that move you through the text and configure your reader, adding books and setting interface preferences (see Figure 5-5). To see your selection of books, click the Library Tree icon on the left. You can organize text by author or tag. On the Options window, the Library tab lets you choose where your books are stored.

Table 5-6

Ebook Readers

Reader	Description
Calibre	Ebook reader and library, also converts various inputs to EPUB ebooks
Ebook reader (Ebook reader)	FBReader ebook reader, search under E-book reader (install with dnf)
Kindle Cloud Reader	Amazon Kindle ebook reader

Calibre reads PDF, EPUB, Lit (Microsoft), and Mobipocket ebooks (see Figure 5-6). Calibre functions as a library for accessing and managing your ebooks. Calibre can convert many document files and ebooks to the EPUB format, the new open source standard used by Apple (iPad) and Amazon (Kindle). It can take as conversion input text, HTML, RTF, and ODT (LibreOffice), as well as ebooks.

GNOME Notes

The GNOME Notes (Bijiben) application lets you create and organize simple notes on your desktop. The Notes window lists your new and recent notes, showing the note title and the first few lines of text (see Figure 5-7). In the header bar, the search button opens a search box that lets you search for notes. The list button lets you switch between icon and list views. The check button lets you delete or organize your notes. A check box is displayed at the lower-right corner of the note icons. Clicking on that check box opens a taskbar at the bottom with buttons to delete the note, add it to a collection (notebooks), or email it. There is also a color button that you can use the background color.

To create a new note, click the New button on the title bar to open a new text. The first line is the title of your note. Press the Enter key to move to the next line (see Figure 5-8). A color button lets you change the background color. The task menu (menu button) provides undo/redo functions, deletion, and email options. You can also add the note to a notebook. You can use notebooks to organize your notes. The share button lets you share the note with other users.

Clocks

Two helpful tools are the clocks and weather applications. Clocks has four tabs: World, Alarm, Stopwatch, and Timer. The World tab displays the current time at any city and at your current location (see Figure 5-9). Click the New button to open a dialog in which you can add a city. To remove a city, click the check button to display a check box in the lower-right corner of each time icon. Check the ones you want to delete, and then click the Delete button. The Alarm tab works as an alarm clock. The Stopwatch tab operates a stopwatch, letting you mark laps. The timer counts down in time. You set the start amount.

Weather

The weather tool lets you display the weather at any city. Click the Places button to open a dialog in which you can enter the name of a city. A partial entry is matched, giving you a listing of possible cities. Choose the one you want. A full image of the weather for that city is displayed, with the temperature and forecast for the next 24 hours, and a sidebar with the forecast for the next several days (see Figure 5-10). To see recently viewed cities, click the Places button to open a dialog where you can choose a city from the Recently Viewed list (see Figure 5-11).

GNOME Text Editor: Gedit

The Gedit editor is the basic text editor for the GNOME desktop. It provides full mouse support, implementing standard desktop operations, such as cut-and-paste to move text, and click-and-drag to select and move/copy text. It supports standard text-editing operations such as Find and Replace. You can use Gedit to create and modify your text files, including configuration files. Gedit also provides more advanced features, such as Print Preview and configurable levels of undo/redo operations, and it can read data from pipes. It features a plugin menu that provides added functionality, and it includes plugins for spell checking, encryption, email, and text-based web page display.

KDE Editor: Kate (KWrite)

The KDE editor Kate provides full mouse support, implementing standard desktop operations, such as cut-and-paste to move text, and click-and-drag to select and move/copy text. The editor is accessible from the Applications ➤ Utilities menu on the KDE desktop, and as KWrite on GNOME. Kate is an advanced editor, with such features as spell checking, font selection, and highlighting. Most commands can be selected by using menus. A toolbar of icons for common operations is displayed across the top of the Kate window. A sidebar displays panels for a file selector and a file list. With the file selector, you can navigate through the file system, selecting files to access. Kate also supports multiple views of a document, letting you display segments in their own windows, vertically or horizontally. You can also open several documents at the same time, moving among them with the file list. Kate is designed to be a program editor for editing software programming/development-related source code files. Kate can format the syntax for different programming languages, such as C, Perl, Java, and XML.

Leafpad

Leafpad is a very simple text editor that provides basic mouse support, letting you edit a file easily (install the leafpad package). It uses an interface similar to Windows Notepad, displaying a menu bar with the File, Edit, Search, and Options menu items. Features are limited to basic operations such as open, save, print, cut, copy, paste, find, and replace.

Nano

To edit a configuration file, you need administrative access, so you first have to use administrative access with the sudo command. Figure 5-12 shows the Nano editor being used to edit the GRUB configuration file, /etc/default/grub.

sudo nano /etc/default/grub

Emacs Editor

The Emacs editor is tailored for program development, enabling you to format source code according to the programming language you use. The versions usually included with Linux distributions are GNU Emacs and XEmacs. GNU Emacs is desktop-capable, with features such as menus, scroll bars, and mouse-based editing operations. You can find more information about Emacs at www.emacs.org and about XEmacs at its website at www.xemacs.org .

The GNU Emacs editor supports basic desktop-editing operations such as selection of text with click-and-drag mouse operations, cut/copy/paste, and a scroll bar for moving through text. The Mode line and Echo areas are displayed at the bottom of the window, where you can enter keyboard commands.

The Vi Editor: Vim and Gvim

The Vim editor included with most Linux distributions is an enhanced version of the vi editor. It includes all the commands and features of the vi editor. Vi, which stands for “visual,” remains one of the most widely used editors in Linux. There are two versions of Vim available, vim-minimal, which is installed by default and provides vi editing capabilities, and vim-enhanced, which provides more advanced features such as Perl and Python interpreters, useful if you use vi to create Perl or Python scripts.

Keyboard-based editors like Vim and Emacs use a keyboard for two different operations: to specify editing commands and to receive character input. Used for editing commands, certain keys perform deletions, some execute changes, and others perform cursor movement. Used for character input, keys represent characters that can be entered into the file being edited. Usually, these two different functions are divided among different keys on the keyboard. Alphabetic keys are reserved for character input, while function keys and control keys specify editing commands, such as deleting text or moving the cursor. Such editors can rely on the existence of an extended keyboard that includes function and control keys.

After executing the vim command , you enter vi’s command mode. Each key becomes a vi editing command, and the screen becomes a window onto the text file. Text is displayed screen by screen. The first screen of text is displayed, and the cursor is positioned in the upper-left corner. With a newly created file, there is no text to display. When you first enter the vi editor, you are in the command mode. To enter text, you must enter the input mode. In the command mode, a is the editor command for appending text. Pressing this key places you in the input mode. Now the keyboard operates like a typewriter, and you can input text to the file. If you press Enter, you merely start a new line of text. With Vim, you can use the arrow keys to move from one part of the entered text to another and work on different parts of the text. After entering text, you can leave the input mode and return to the command mode by pressing Esc. Once you’ve finished with the editing session, you exit vi by typing two capital Zs, ZZ. Hold down the Shift key and press Z twice. This sequence first saves the file and then exits the vi editor, returning you to the Linux shell. To save a file while editing, you use the line-editing command w, which writes a file to the disk. w is equivalent to the Save command found in other word processors. You first type a colon to access the line-editing mode and then type w and press Enter, :w.

You can use the :q command to quit an editing session. Unlike the ZZ command, the :q command does not perform a save operation before it quits. In this respect, it has one major constraint. If any modifications have been made to your file since the last save operation, the :q command will fail, and you will not leave the editor. However, you can override this restriction by placing a ! qualifier after the :q command. The command :q! will quit the vi editor without saving any modifications made to the file during that session (the combination :wq is the same as ZZ).

To obtain online help, enter the :help command. This is a line-editing command. Type a colon, enter the word help on the line that opens at the bottom of the screen, and then press Enter. You can add the name of a specific command after the word help. Pressing the F1 key also brings up online help.

As an alternative to using Vim in a command-line interface, you can use gvim, which provides X Window System–based menus for basic file, editing, and window operations.

The package vim is called the vim-X11 package , which includes several links to Gvim, such as evim, gview, and gex (open Ex editor line). To use Gvim, you can enter the gvim command at a terminal prompt. The standard vi interface is shown, but with several menu buttons displayed across the top, along with a toolbar with buttons for common commands like search and file saves. All the standard vi commands work as described previously; however, you can use your mouse to select items on these menus. You can open and close a file, or open several files, using split windows or different windows. The editing menu enables you to cut, copy, and paste text as well as undo or redo operations.

In the editing mode, you can select text with your mouse with a click-and-drag operation or use the Editing menu to cut or copy and then paste the selected text. Text entry, however, is still performed using the a, i, or o commands to enter the input mode. Searches and replacements are supported through a dialog window. There are also buttons on the toolbar for finding next and previous instances. You can also split the view into different windows to display parts of the same file or different files. Use the :split command to open a window, and use :hide to close the current one. Use Ctrl+w with the up and down arrow keys to move between them. On Gvim, you use entries in the Windows menu to manage windows. Configuration preferences can be placed in the user’s .vimrc file.

Evolution

Evolution is the primary mail client for the GNOME desktop. Although it’s designed for GNOME, it works equally well on other desktops. Evolution provides a mail client, calendar, and address book. The mailer supports several protocols (SMTP, POP, and IMAP), multiple mail accounts, and encryption. It also supports Pretty Good Privacy (PGP) and GNU Privacy Guard (GPG) encryption. Messages are indexed for easy searching. Junk mail filtering is provided. See the Evolution website ( https://wiki.gnome.org/Apps/Evolution ) for a complete description of its features.

You can access Evolution from the Applications overview. The Evolution mailer provides a simple desktop interface, with a toolbar for commonly used commands and a sidebar for shortcuts. A set of buttons on the lower left allows you to access other operations, such as the calendar and contacts. The mail screen is divided into two panes, one for listing the mail headers and the other for displaying the currently selected message (see Figure 5-13). You can click any header title to sort your headers by that category. Evolution also supports the use of virtual folders created by the user to hold mail that meets specified criteria. Incoming mail can be automatically distributed to a particular virtual folder.

To configure Evolution, select Preferences from the Edit menu (Edit ➤ Preferences). On the Evolution Preferences window, a sidebar shows icons for mail accounts, contacts, mail preferences, composer preference, network preferences, calendar and tasks, and certificates. The main accounts entry displays a list of current accounts. An Add button lets you add new accounts, and the Edit button allows you to change current accounts.

Numerous plugins are available to extend Evolution’s capabilities. Most are installed and enabled for you automatically, including the SpamAssassin plugin for handling junk mail. To manage your plugins, select the Plugins entry in the Edit menu (Edit ➤ Plugin) to open the Plugin Manager. The plugins are listed in a left scroll window, and the configuration tabs for a selected plugin are on the right.

Evolution also supports contact operations such as calendars, contact lists, and memos. On the left-side pane, the bottom section displays buttons for these different functions: Mail, Contacts, Calendars, Tasks, and Memos. To see and manage your contacts, click the Contacts button on the left sidebar. The Calendar displays a browsable calendar on the left pane to move easily to a specific date. The right pane shows a daily calendar page by the hour, with sections for tasks and memos. You can set up several calendars, which you can access at the top of the right pane. A personal calendar is set up for you already. To add a new calendar, select Calendar from the New menu. This opens a New Calendar dialog, from which you can choose the type and name.

Thunderbird

Thunderbird is a full-featured standalone email client provided by the Mozilla project ( www.mozilla.org ). It is designed to be easy to use, highly customizable, and heavily secure. It features advanced intelligent spam filtering, as well as security features such as encryption, digital signatures, and S/MIME. To protect against viruses, email attachments can be examined without being run. Thunderbird supports both the Internet Message Access Protocol (IMAP) and the Post Office Protocol (POP). It also functions as a newsreader and features a built-in RSS reader. Thunderbird also supports the use of the Lightweight Directory Access Protocol (LDAP) for address books. Thunderbird is an extensible application, allowing customized modules to be added to enhance its capabilities. You can download extensions such as dictionary search and contact sidebars from the website.

Thunderbird provides integration with popular online mail services like Gmail, saved searches, and customized tags for selected messages. You can access Thunderbird from the Applications overview.

The Thunderbird interface uses a standard three-pane format, with a side pane for listing mail accounts and their mailboxes (see Figure 5-14). The top pane is the message list pane, and the bottom pane shows a selected message’s text. Commands can be run using the toolbar, the tool menu (button at the right of the toolbar), or keyboard shortcuts. You can even change the appearance using different themes. Thunderbird also provides a Tasks tab and Calendar tab for scheduling events and noting dates. Upcoming tasks are listed on the main window on a sidebar on the right.

To edit an email account, select the Preferences ➤ Account Settings from the menu opened by the menu button at the right of the toolbar. In the Account Settings window, you will see an entry for your mail account, with tabs for Server Settings, Copies & Folders, Composition & Addressing, Offline & Disk Space, Return Receipt, and Security. The Server Settings tab has entries for your server name, port, username, and connection and task configurations, such as when to check for messages. The Security tab shows a Manage Certificates button, which opens the Certificate Manager, from which you can select security certificates to use to digitally sign or encrypt messages.

Thunderbird provides an address book in which you can enter complete contact information, including email addresses, street addresses, phone numbers, and notes. Select the Address Book button on the toolbar to open the Address Book window.

GNOME Contacts

If you have enabled contacts for Online Accounts, you can use the GNOME Contacts application to manage and access those contacts (see Figure 5-16). Contacts are downloaded from the enabled online accounts. Currently, only Google is supported. You can then access and edit those contacts with the Contacts application, which is accessible from the Applications overview. First be sure to switch on Contacts in System Setting’s Online Accounts (see Figure 5-15).

Contacts displays a sidebar listing your contacts. A search box lets you search for contacts. To add a contact manually, click the plus button (+) above the search box (see Figure 5-16). The selected contact shows the name, icon used, and the email address. The email entry is a mail button, which you can click to open your mailer to compose a message to be sent to that address.

To edit the contact information, click the edit button (pencil icon) at the top-right corner. You then can edit entries or provide additional information, such as the address, phone, links, website, birthday, and notes (see Figure 5-17). For each entry, you can classify whether it is work, home, or other. To remove a contact, click the Remove Contact button at the lower right. You can also remove the contact by clicking on its entry in the sidebar to display a check box , which, when clicked, displays a Remove button at the bottom of the sidebar.

The KDE Mail Client: KMail

The KDE mail client, KMail, provides a full-featured desktop interface for composing, sending, and receiving email messages. KMail is part of the KDE Personal Information Management suite (KDE-PIM), which also includes an address book (KAddressBook), an organizer and scheduler (KOrganizer), and a note writer (KNotes). All these components are directly integrated on the desktop into Kontact. You can start up KMail directly or as part of the Kontact applications (Mail). KMail, along with Kontact, KOrganizer, and KAddressBook, is accessible from the KDE Desktop Office and Internet menus. On GNOME, you can access it from Applications overview. You can access Kontact in the Office filter. KMail is installed as part of the KDE desktop, but you can install it separately.

To quickly set up a new email account, you can use the Account Wizard (Tools ➤ Account Wizard). A series of dialogs will prompt you to enter the account type, the account name and address, a login name and password, and the incoming and outgoing servers. For more detailed configuration, select the Configure Kmail entry in the Settings menu (Settings ➤ Configure Kmail).

Emacs Mail

The GNU version of Emacs includes a mail client, in addition to other components, such as a newsreader and editor. GNU Emacs is included on Fedora distributions. Check the Emacs website at www.gnu.org/software/emacs for more information. When you start GNU Emacs, menu buttons are displayed across the top of the screen. If you are running Emacs in an X Window System environment, you have full desktop capabilities and can select menus using your mouse. To access the Emacs mail client, select from the mail entries in the Tools menu. To compose and send messages, just select the Send Mail item in the Tools menu.

Command-Line Mail Clients

Several mail clients use a simple command-line interface. They are simple and easy to use but include an extensive set of features and options. Two of the more widely used mail clients of this type are Mail and Mutt. Mail is the mailx mail client that was developed for the UNIX system. It is considered a default mail client that can be found on all UNIX and Linux systems. Mutt is a cursor-based client that runs from the command line.

Accessing Mail on Remote Mail Servers

Most new mail clients are equipped to access mail accounts on remote servers. Mail clients, such as Evolution, KMail, Sylpheed, and Thunderbird, enable you to set up a mailbox for such an account and access a mail server to check for and download received mail. You must specify what protocol a mail server uses. This is usually either the Post Office Protocol (POP) or the IMAP protocol (IMAP). Using a mail server address, you can access your account with your username and password.

To have Fetchmail run automatically, you can set the START DAEMON option to yes in the /etc/default/fetchmail file.

You can specify options, such as the server type, username, and password, in a .fetchmailrc file in your home directory. You can also include entries for other mail servers and accounts. Once Fetchmail is configured, you can enter fetchmail with no arguments; it will read entries from your .fetchmailrc file. You can also make entries directly in the .fetchmailrc file. An entry in the .fetchmailrc file for a particular mail account consists of several fields and their values poll, protocol, username, and password. The poll field refers to the mail server name. You can also specify your password, instead of having to enter it each time Fetchmail accesses the mail server.

Mailing Lists

Users on mailing lists automatically receive messages and articles sent to the lists. Mailing lists work much like a mail alias, broadcasting messages to all users on the list. Mailing lists were designed to serve specialized groups of people. Numerous mailing lists, as well as other subjects, are available for Linux. By convention, to subscribe to a list, you send a request to the mailing list address with a –request term added to its username. For example, to subscribe to [email protected], you send a request to [email protected].

You can use the Mailman program to manage your mailing lists automatically. Mailman is the GNU mailing list manager that is included with Fedora. You can find out more about Mailman at www.list.org .

SQL Databases (RDBMS)

SQL databases are relational database management systems (RDBMSs) designed for extensive database management tasks. Many of the major SQL databases now have Linux versions, including Oracle, Informix, Sybase, and IBM. These are commercial and professional database management systems. Linux has proved itself capable of supporting complex and demanding database management tasks. In addition, many free SQL databases are available for Linux that offer much the same functionality. Most commercial databases also provide free personal versions.