To rob a person is to take a thing from him by force.
To steal is to take a thing secretly.
1. Some merchants coming in a lorry were robbed by some highway-men on the way of Bihar.
2. I have been robbed.
3. He robbed a bank.
1. My fountain pen has been stolen,I do not know by whom or how.
2. He was expelled from the school because he had been stealing.
3. Thieves broke into the house and stole money and jewellery.