We can see whether there are any updates available for the packages installed on our system by executing the command line, as shown here:

$ yum check-update

We can also update an installed application and its dependencies to the latest stable version using the yum command. In this process, YUM preserves the existing configuration files, except in cases where it is mandatory to update the configuration file for working on an updated version of the application, as shown in command line here:

$ yum update httpd

We can update our system and installed application together in a single command by not specifying any application name to the yum update command, as shown in command line here:

$ yum update

While updating the system or application, all applications except the kernel are updated immediately at runtime. The latest kernel version comes into effect only after rebooting the system. We can use the uname -r command to view the running kernel version.