Electrical Safety Devices

1.RCCB/RCD -Residual current circuit breaker or RCD -Residual current device.
               Trips when earth is at fault
                Shock protection
                 better for humans
                 best to detect earthing problems
  ELCB is older name and voltage based
  RCCB is newer current based
        
2.MCB- Miniature circuit breaker
3.MCCB - Moulded case circuit breaker
                [MCB are glorified fuse's , a fuse box that trips and
                 can be reset rather than change  a burnt wire,an electromechanical
                 device ]
                
                     2 and 3 are better for overload protection and devices

4.RCBO  is combination of MCB and RCD