In the world of CPUs, the x86 and newer x64 are the most common architecture types used with laptops. The x86 can only have a reserve of up to 4GB RAM whereas the x64 can access more than this, making it more powerful. Meanwhile, AArch64 (or ARM64) is a 64-bit extension of ARM architecture that can access more than 4GB RAM. However, it isn't as powerful as x86 or x64 architecture. ARM64 has traditionally been utilized in smartphones and smaller devices, but it's being used more and more with laptops and tablets as time goes on.