To my knowledge cross-correlation is used to measure the similarity of certain values, like to images. Same applies to the process of feature extraction in CNNs, where input matrices are multiplied by filters. So it seems odd to me that they are call Convolutional Networks.
The Pytorch documentation for Conv2d even says that it is using the cross-correlation operator.
So why are CNNs called convolutional when they are actually using cross-correlation?