There are various operating systems, such as Linux, that are used by the cloud and many network appliances, and Microsoft has Windows 10 for desktops and laptops, and Server 29016 for servers. There is also Android for many phones, as well as Apples iOS for iPhones and iPads. Let's look at different uses of these:

• Network: Network devices such as switches, routers, and firewalls all have some sort of operating system installed so that they can be configured. Normally, these are different versions of Linux, such as FreeBSD, Red Hat, CentOS, or Ubuntu.
• Server: A server operating system needs to be secure as these can be used for databases such as SQL server or a mail server, such as Exchange 2016. The domain controller runs on operating systems such as Server 2016 and has a secure boot.
• Workstation: Workstation operating systems such as Windows 10 are the most secure client operating systems. Windows 10 has a secure boot and has the ability to use Bitlocker, a version of FDE to protect against data theft.
• Appliance: Security appliances are firewalls, intrusion detection systems, and intrusion detection systems are used to protect against attacks.
• Kiosk: A Kiosk is a computer in a reception area or foyer; it is used to gain access of the building that you are visiting. Their functionality is limited and they would normally be a workgroup and not connected to the network.
• Trusted operating system: A trusted operating system is a secure system normally used by the military where it has multiple layers of security, as it is used to access classified data. It is tied down tightly and changes to the operating system as controlled.
• Mobile OS: Apple iOS is an operating system for mobile devices, such as the iPhone and the iPad, and Android is used by all other mobile telephones, such as Samsung.