[AC Question]

How to hide pictures

[Rukbat]

Create a file in the folder the pictures are in. Name it .nomedia (nothing to the left of the dot). There doesn't have to be anything in the file, although there can be. Just a file of that name in the folder tells Media Scanner to ignore the folder. If Media Scanner can't find the pictures, Gallery won't show them.

(If you mean "hide from prying eyes", there's not enough space in a forum answer to teach you how to obfuscate pictures so no one can unobfuscate them enough to see them. Maybe a good 2-key encryption app would help.)