Find...
Opens the Find Window and its "Find" tab, with which one can search in the current file.
Find in Files...
Opens the Find Window and its "Find in Files" tab, with which one can search in any file and display the results in the "Find Results" near the bottom of the screen.
Replace...
Opens the Find Window and its "Replace" tab, with which one can replace in the current file.
Replace in Files...
Opens the Find Window and its "Replace in Files" tab, with which one can replace in any file.
Search Again
Repeats the previous Find or Find in Files command. If the previous command was a Find command, the new search is started from the cursor in the forward direction.
Search Again Backwards
Repeats the previous Find or Find in Files command. If the previous command was a Find command, the new search is started from the cursor in the backward direction.
Incremental Search
Opens up a text box that performs an search-as-you-type search, just like in browsers.
Goto Function...
Brings up a dialog that lists all available functions and allows you to search through them and navigate to them by clicking them.
Goto Line...
Brings up a dialog that allows one to enter a line number and navigate to it.