That's true, but I guess one should then mention a 5 digit number would consume less space in memory than in textual format. MsgPack recognizes this and stores

That's true, but I guess one should then mention a 5 digit number would consume less space in memory than in textual format. MsgPack recognizes this and stores that 5 digit number using the minimum number of bits required, but this wouldn't be possible in the usual json string formats.