The differences between different types of sockets for AMD & Intel

[VcBoy87]

Yeah, like my title says, whats the difference between all the sockets processors use these days? I see all these types of sockets and I'm just curious as to what each one does specifically or was meant for, if anything.

So like what do each of these do or whats their differences?

LGA 775
Socket 478
Socket 604
Socket 754
Socket 939
Socket 940
and Socket A

Thanks in advance.