Delete
delete word
dw -> delete until the start of next word
de -> delete after the end of current word
db -> delete to beginning of current word
d2w -> delete until start of 2ed word
delete line
d0 -> delete to line front
d$ -> delete to line end
dd -> delete current line
2dd -> delete 2 lines
delete file
:%d -> delete the whole file
dgg -> delete to the beginning of the file
dG -> delete to the end of the file
change
ce -> delete to word end and insert
c2w -> delete to 3rd word front and insert
c3e
c0
c$