Just like Windows ..
.. Linux supports several different types of filesystems. Support for a filesystem is provided by the kernel, through resident software that is built-in to the kernel or
through loadable kernel-modules, or both.
(In Windows, the analog feature is called IFS
= Installable File Systems.)
is probably the most commonly used system. It's based on "ext2" but also has journaling,
which allows it to recover very quickly from errors if the system crashes.
is gaining popularity because it stores "thousands of very small files" very efficiently... and in an awful lot of practical situations, that is what we are usually dealing with. It also supports journaling.
CD-ROMs and other external media commonly use other filesystems that may only be found on these types of devices.