amd64 is the name for the architecture that both intel and amd use in their 64-bit desktop processors. It has that name because it was originally amd that released the architecture (and intel used itanium at the time).
"After launching the architecture under the "x86-64" name, AMD renamed it AMD64 in 2003; Intel initially used the names IA-32e and EM64T before finally settling on Intel 64 for their implementation. x86-64 is still used by many in the industry as a vendor-neutral term, while others, notably Sun Microsystems (now Oracle Corporation) and Microsoft, use x64."
Also, I'm not too familiar with it, so why does it imply that the 64 bit version only works on AMD CPU's? Is there no 64 bit version for Intel?