1. Metal/wire cages

Advantages:
- Durable and chew resistant.
- Bars allow hamster to climb on.
- Allow air to circulate more freely.
Disadvantages:
Temperatures fluctuate more drastically as metal can get very cold or very hot depending on the temperature it is exposed to.
Litter and food tend to scatter as the hamster likes to burrow and move around the cage.
Metal cages with wire bottoms are not suitable for hamsters as their tiny feet may get caught in the wire.
The wires are susceptible to rusting, especially if your hamster likes to chew on them.
When buying such cages, opt for one with a non-wire bottom so that your hamster's feet will not get caught at the base. A wire cage with a deep plastic base also reduces the amount of litter and food that is scattered.