The unique name of any file is composed of a drive letter, a directory path, and a filename. In Windows, each of these parts of the file's name is case insensitive; you can mix upper and lower case letters in any way you wish. (Note that when accessing Linux / UNIX FTP servers, the filenames are case sensitive.)
The topics below are roughly divided according to the different parts of a file name, and cover the file system structure and naming conventions:
Executable Files & File Searches
Directories and Subdirectories