The basic commands for deleting text are ...
DEL delete the character just before the cursor
C-d delete the next character after the cursor
M-DEL kill the word immediately before the cursor
M-d kill the next word after the cursor
C-k kill from the cursor position to end of line
M-k kill to the end of the current sentence
Note: One C-K will delete to the end of the line, but will not remove the new-line. A second C-K is needed to kill the new-line.
Some the above commands delete text, and others kill text. Deleted text is gone for good. Killed text is placed into a kill ring that can be yanked back into the file.
To retrieve killed text, move the cursor to the point in the file where you want the text to go, and type C-Y (yank).
C-Y Yank killed text back in to the file.
NOTE: The emacs meaning for yank is exactly the opposite of the meaning that VI uses.