Question

Please explain what a tab stop is and its primary purpose.

Answer 1

please help, I don't fully understand Tab Stop

Answer 2

in which context, did u encounter with this 'Tab stops'?

Answer 3

http://www.computerhope.com/jargon/t/tabstop.gif
the space between those two L's in word processors, for example, are tab stops .
tab stops are just whitespaces of some length.
if you press space then cursor will advance through one position meaning that it has whitespace or length 1 .
like wise when tab key is pressed in keyboard, cursor advances more than the space advanced by space ( mostly four white spaces equalling the pressing of space four times)
in some contexts, tab stops are discussed in indentation where indented line is first starts with tab stop.