Explain the terms suid, sgid and sticky bit ?

In addition to the basic file permissions in Linux, there are few special permissions that are available for executable files and directories.

SUID : If setuid bit is set, when the file is executed by a user, the process will have the same rights as the owner of the file being executed.

SGID : Same as above, but inherits group previleges of the file on execution, not user previleges. Similar way when you create a file within directory,it will inherit the group ownership of the directories.

Sticky bit : Sticky bit was used on executables in linux so that they would remain in the memory more time after the initial execution, hoping they would be needed in the near future. But mainly it is on folders, to imply that a file or folder created inside a stickybit enabled folder could only be deleted by the owner. A very good implementation of sticky bit is /tmp ,where every user has write permission but only users who own a file can delete them.