Just what is the deal with AMD and Intel?

How is it that Intel provide processors at one frequency, and Amd provide them at a lower frequency – and claim them to be equivalent products…?

It seems insane, however there are many hundreds of ways different processors can outshine eachother. For example all processors have an onboard cache of fast access memory on-board, cryptically called an on board cache. This stores instructions, input values and a stack of results which the processor or processors can process and store to, among other things.