Hub:

--It is a layer 1 device.

-- Just Flood every data it receives [ don't maintain any table ] 

--Usually, have 4 or 8 ports.

--One Collision Domain and One BroadCast Domain.

-- All devices connected with hub operates in Half-Duplex.

Switch:

--It is a layer 2 device.

--It forwards data on the basis of mac address table by looking at Destination mac of frame.

--Switches have 24 or 48 or more number of ports.

-- Per-Port Collision Domain and One Broadcast Domain.

[ We can use Vlan to divide brodcast domain of switch ]

--Switches can work in Hal-Duplex or in Full-Duplex.