Take a screenshot on a Windows 7 (older) computer: https://www.youtube.com/watch?v=h6hE9_9OlQo
Take a screenshot on a Windows 10 computer: https://www.youtube.com/watch?v=tirNbkEXZII
Take a screenshot on a Mac: https://www.youtube.com/watch?v=89GA6a4lAn4
Take a sceenshot on an iphone: https://www.youtube.com/watch?v=MQhTF6531PQ
Take a screenshot on a samsung galaxy: https://www.youtube.com/watch?v=cw7TXJO5aTg