logical shift: all bits move towards left pr right including the sign bit.. generally used in serial data communication to transfer the data bit by bit or for multiplying unsigned numbers by power of 2.
Arithmetic shift:all bits move towards left or right except the sign bit.. used in signed arithmetic computations..
ex: 10100110
after logical left shift:01010011
arithmetic left shift: since MSB is signed bit.. so msb will not shift.. 10010011..