All the devices connected with hub (which is layer 1 device) are in same collision domain and broadcast domain as hub just repeats the signal received at one port and sends it to the other port, does not perform any switching or routing.
Switches and Bridges (Layer 2 devices) are used to break the network in segments. Each segment forms a separate collision domain but all devices irrespective of their segment receives broadcast message so these are in same broadcast domain.
Router (Layer 3 Device) segments network in separate collision domains and broadcast domains.