Here are some ways robots can be useful :

Advantages
1) Going to far away planets
2) Spying on people in ways people can't move and from views humans can't reach
3) Going far down into the unknown waters where humans would be crushed
4) Giving us information that humans can't get
5) Working at places 24/7 without any salary and food. Plus they don't get bored
6) They can perform tasks faster than humans and much more consistently and accurately
7) They can capture moments just too fast for the human eye to get, for example the Atlas detector in the LHC project can capture ~ 600000 frames per second while we can see at about 60
8) Most of them are automatic so they can go around by themselves without any human interference
9) They can entertain us and help us in certain tasks

Disadvantages
1) People can lose jobs in factories
2) It needs a supply of power
3) It needs maintenance to keep it running
4) It costs money to make or buy a robot




Dancing Robots
Dancing Robots



Sony's QRIO Robot
Sony's QRIO Robot


It can hold fans
It can hold fans


A robot carrying an injured soldier
A robot carrying an injured soldier


Walking Asimo
Walking Asimo

Asimo Playing Football
Asimo Playing Football

Sony's Qrio Dancing
Sony's Qrio Dancing