4-4 point low approach attach
In this position, used to be considered joseki, and was one of the most popular joseki taught to beginners, but has been a bit less popular in recent years. The AI revolution has cast doubt on whether it is generally a good move, but it is still seen in professional games in 2019.
- e the stretch &peep has previously been criticised, but is nowadays preferred by AI in some contexts. See Noseki - 4-4, low approach, attach on top, peep.
- d, see BQM 97.
- a move like f does not put enough pressure on the attaching stone and allows Black to play the bulge at e.