Registers hold the operands or instruction that CPU is currently processing.Memory holds the instructions and the data that the currently executing program in CPU requires.
Register holds the small amount of data around 32-bits to 64-bits.Memory of the computer can range from some GB to TB.
CPU can operate on register contents at the rate of more than one operation in one clock cycle.CPU accesses memory at the slower rate than register.
Types are Accumulator register, Program counter, Instruction register, Address register, etc.Type of memory are RAM, etc.
Registers can be control i.e. you can store and retrieve information from them.Memory is almost not controllable.
Registers are faster than memory.RAM is much slower than registers.