Today is Good Knee Socks Day in Japan, a day to celebrate cute anime girls wearing knee-high socks. Check out the best anime girls wearing socks in this blog post!
It's even tagged as zettai ryouiki, when most of the examples are absurdly off from the correct ratio. To quote wikipedia:
The ideal zettai ryōiki ratio for the length of the miniskirt, the exposed portion of thigh, and the over-knee part of the socks is 4:1:2.5, with a tolerance of 25%.[3][4][5] The ratio has also been referred to as a golden ratio (黄金比, ōgonhi) among fans.[6]