It helps to understand the lingo before getting started. A lot of this will be familiar to you from other operating systems such as Microsoft Windows, but there are some differences that you’ll need to get used to as well. To start, the word “filesystem” is actually used in more than one way. The general use (and what I am typically referring to throughout the book when I use this term) means “the files and directories (or folders) you have access to right now.”
The first major difference to be aware of is that Linux uses a forward slash (/) between directories, not the backslash (\) that Windows does. So, the file yum.conf in the directory etc is etc/yum.conf. Files and directories can have names up to 256 characters long, and these names can contain underscores (_), dashes (-), and dots (.) anywhere within, even more than one. So my.big.file or my.big_file or my-big-file are all valid filenames.
Upper and lowercase also matter quite a bit. They have to match exactly. The file yum.conf and Yum.conf are not the same as far as Linux is concerned. Finally, the same filesystem can span over multiple partitions, hard drives, and media such as CD-ROM drives. You just keep going down through subdirectories, not having to care if something is on disk A, B, or whatever. This issue will be addressed in the section “Partitions versus Directories” later in this chapter.