Deletion and Killing ==================== Most commands which erase text from the buffer save it in the kill ring so that you can move or copy it to other parts of the buffer. These commands are known as "kill" commands. The rest of the commands that erase text do not save it in the kill ring; they are known as "delete" commands. (This distinction is made only for erasure of text in the buffer.) If you do a kill or delete command by mistake, you can use the `C-x u' (`undo') command to undo it (Note: Undo). You cannot kill read-only text, since such text does not allow any kind of modification. But some users like to use the kill commands to copy read-only text into the kill ring, without actually changing it. If you set the variable `kill-read-only-ok' to a non-`nil' value, the kill commands work specially in a read-only buffer: they move over text, and copy it to the kill ring, without actually deleting it from the buffer.