Because CD is short for "Change Directory"
The 'CD' command is not standard for Unix. The 'cd' command, however, will change directories (folders). It is a means of navigating the Unix file system.
dig
nslookup
In Windows and Unix-based and Unix-like systems, the command is mkdir (however in Windows a shortcut md can be used as well).
Believe it or not, nslookup.
UNIX is a command-based OS. In contrast, Windows is a menu-based OS.
A Unix shell can be obtained in Cygwin, a Unix compatibility layer used to compile Unix programs and run them on Windows. Microsoft also makes a shell known as "Windows PowerShell" which incorporates more Unix-like features than the standard command prompt.
The shell interpreter uses the PATH or path variable to determine which directories to look in. It will look for an executable file with the same name as the command.
Because Linux was modeled after Unix, and designed to be a suitable free replacement. Windows is targeted at a slightly different market, and was primarily designed to be operated using a GUI, not the command line.
The 'type' command does approximately (but not exactly) the same thing as the 'cat' command.
Use the command 'passwd'
passwd