I understand that bias (in the context of bias-variance tradeoff) is "the expectation of the difference between the true, and estimated, parameters". However, I would like to understand who is biased and towards what. There are many articles which clearly explain what bias is, but this point is not mentioned.

Could someone please help with this question?

I understand that bias (in the context of bias-variance tradeoff) is "the expectation of the difference between the true, and estimated, parameters". However, I would like to understand who is biased and towards what. There are many articles which clearly explain what bias is, but this point is not mentioned.