The 4-4 point is the corner star point (aka hoshi) on a 19x19 board, indicated by a bold dot.
A stone on the 4-4 point strikes a balance between outward influence / potential for development and defence of the corner.
The corner is not secure, but if Black takes the corner (for example by invading at a), White is guaranteed a large amount of influence.
However, the high position of the stone means that good extensions can be based on it. Unlike the 3-4 point, there are no urgent moves to be played to stabilise the hoshi stone. White will be more likely to play a far extension on the left or upper side rather than to play a second move near the corner.
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