25 key joseki.
I’ve tried to choose the most simple and common variations. The circle represents an optional continuation by the player who has sente from the diagram (not that they have to play it immediately.)
Notes:
#2 is a post-bot sequence, superseding the pre-bot slide (although the slide is still absolutely playable.)
#3 is a slight post-bot shift from the pre-bot variation in which (10) was the solid connection between (8) and (4). There is some important difference in the nature of the shape weaknesses.
#4: pre-bot sequence, looking like it may be slowly falling out of use in favour of other similar variations.
#5: pre-bot sequence, now seeming to be getting replaced by a post-bot variation which omits the (3) for (4) hane exchange.
#9 is on the border of what constitutes a joseki and may be bad for White in the early game. The advantage of this is to avoid entering either of two complex variations.
#14 is standing in for all low-approach pincers, but actually in larger pincers the push-and-cut response (as seen in #15) can start a complicated fight. Still, the one-space jump isn’t simple either if White wants a good result.
#17: I recommend not to play this as White unless you are happy entering the complex “small avalanche” variation that Black can begin by playing (6) at (7). In this simple variation White’s shape can also be difficult to work with.
#23: (4) at (5) is also common, and is more difficult. So it may be worth thinking twice about invading 5-4 at 3-3.
#25: There is also a harder variation beginning with (6) at (5). It’s fine not to play this forcing move if you’d rather not have to enter that.