Sleep is a Windows Scripting Host command (like JScript or VBScript). It's not really a cmd-interpreted batch thing.
Timeout is like a pause that auto continues after a specified time or on keypress (unless the /nobreak switch is used).
There's also waitfor, which pauses for X seconds or until a signal is received from another computer or window.
timeout and waitfor are included with Windows 7 and newer. For compatibility with earlier versions of Windows, traditionally, ping is used to simulate a pause like this:
ping -n 6 0.0.0.0 >NUL
... will pause for 5 seconds. (-n 6 means ping 6 times. The first ping response is instant, so N+1 is needed to pause N seconds.)
Some people also use choice /t to pause. See the How to sleep for 5 seconds in Windows Command Prompt related page if you'd like. There may be a reference to a utility or resource kit there you've installed that makes Sleep work on your Win 7 laptop, which has not been installed on your 8.1 desktop.