Delete (cut) to end of line and start inserting new text
Default keystroke(s): C
Start entering text on new line before current line
Default keystroke(s): O
Delete (cut) current line and begin inserting text
Default keystroke(s): S
Delete (cut) range and start inserting new text
Default keystroke(s): c
Start entering text on new line after current line
Default keystroke(s): o
Delete (cut) character under cursor and begin inserting text
Default keystroke(s): s