Clearing the screen

CLS
CLS command clears the screen.
Syntax
CLS
The CLS command is invoked without parameter. It will erase all character DOS prompt on the top of screen.
Example 1
C:\>CLS 
It clears the screen leaving the DOS prompt (i.e. C:\>)

Version of DOS
VER
It displays the current DOS version number.
Syntax
VER
The VER command has no additional option switches.
Example 1
C:\>VER 
If you want to know what version of MS-DOS you are using, you simply type VER and press enter key, it displays the version number on your screen.