Vim

Question 1

write and quit (save file and exit)

Answer 1

:wq

Question 2

undo

Answer 2

u

Question 3

jump forwards to the start of a word

Answer 3

w

Question 4

jump forwards to the end of a word

Answer 4

e

Question 5

delete (cut) a line

Answer 5

d

Question 6

delete (cut) character

Answer 6

x

Question 7

jump backwards to the start of a word

Answer 7

b

Question 8

repeat last command

Answer 8

.

Question 9

delete marked text

Answer 9

d

Question 10

switch case

Answer 10

~

Question 11

insert before the cursor

Answer 11

i

Question 12

insert at the beginning of the line

Answer 12

I

Question 13

insert (append) after the cursor

Answer 13

a

Question 14

insert (append) at the end of the line

Answer 14

A

Question 15

append (open) a new line below the current line

Answer 15

o

Question 16

append (open) a new line above the current line

Answer 16

O

Question 17

insert (append) at the end of the word

Answer 17

ea

Question 18

exit insert mode

Answer 18

Esc or Ctrl + c

Question 19

search for pattern

Answer 19

/pattern

Question 20

write (save) and quit

Answer 20

:wq or :x or ZZ

Question 21

quit and throw away unsaved changes

Answer 21

:q! or ZQ