Definicija :
The system path is a list of folders, separated by a semicolon, that identifies the folders that the system should search when looking for files that are called from the Run dialog box, command line, or other processes. Normal program installation changes this path to include the program’s installation path.
PATH may be set on a system and user level.
An alternative to setting the path at system level is to change it at user level; however, doing so will affect only your logon session and not other users who might use the computer or system processes, which might cause confusion and unexpected behavior.

Kako se menja PATH promenljiva :
1. Go to : Start – Settings – Control Panel – System
2. Select the Advanced tab.
3. Click the Environment Variables button.
4. Under System Variables, select Path, then click Edit.
You’ll see a list of folders, as this example shows: C:\Program Files\Windows Resource Kits\Tools\;%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;C:\Program Files\Support Tools\;C:\Program Files\Common Files\Roxio Shared\DLLShared;C:\Program Files\Common Files\Ulead Systems\MPEG;C:\Program Files\Intel\DMIX;C:\Program Files\Executive Software\Diskeeper\;C:\Program Files\Bonjour\;C:\Program Files\QuickTime\QTSystem\;C:\Program Files\Misc
You can add additional folders that you want to include in searches, with “;” at the beggining and at the end. Click OK.
You’ll need to restart the processes (e.g., command prompt) that use the system path to see the added folders.

Napomena1 : ako u Start/”Run” ukucate “Environment” (bez navodnika), dobićete spisak svih promenljivih okoliša u kojem radite.
Napomena2 : WIN 2012 NEMA PATH varijablu, pa se samo ona doda na istom mestu kao što je gore navedeno.

Odakle sam uzela (i testirala) gore navedeno : link1. Još jedan dobar link2.