Clip is a command used to Copy contents of the out put from the command prompt into the clipboard. Example : The command DIR Will List all the ditrectories in the Location you are pointing to in the command Prompt. If you want to copy the output type the command as DIR | CLIP. You will not find any output being displayed in the command Prompt, but the contents will get copied into the Clipboard. Just Open the Notepad and paste. There you go !
In windows you can search for keyboard from start menu and open keyboard settings. Or you can go to Settings > Accessibility > Keyboard. In the keyboard settings window, toggle the switch that says "Use the Print screen button to open screen snipping". Hereafter whenever you press print screen button, you will be able to make a selection on the screen for a screenshot.