A non-spacing character, when typed, doesn't move the entry point to the next character, as in conventional typewriters where to type an 'ä' one must type the umlaut (¨) first and then 'a' which will go into the same space.

In computer input non-spacing characters start a non-spacing character sequence. Valid nonspacing character sequences are restricted to combinations of diacritical marks and alphabetic characters. Nonspacing character sequences are folded into a single character before passing the keyboard input to the application.