Common 2-2 joseki, I'm surprised you don't know it. White plays
for influence. He usually has a 4-4 or 5-4 stone in the opposite corner when playing such a move. Black responds at
to counter this strategy while white plays the shoulder hit at
to again try for influence. At this point, black is happy to get some fourth line territory, and white is happy to gain his influence (usually pushing along with
and
). Clearly (a) will be a key point in this position later.
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