Peter was an apostle of Jesus Christ and was one of the twelve disciples.
He was formally known as Simon but Jesus changed his name after he became a disciple.
Paul was a blasphemous christian hater. He was a leader of the atheists until he became an apostle of Christ, but before then he was called Saul. He killed many christians on his reign of terror.
Peter's call to be an apostle happened in the region of Gennesaret. Jesus was preaching to hundreds of believers including Simon, who had been fishing all night without catching anything. Jesus then came to Simon and hopped into his boat. He told Simon to go into the middle of the lake and cast out his nets. Simon said he had been working hard all night but did it because Jesus said so. He immediatley began catching fish, so many that his nets began to brake. They had to call over other boats to carry the fish because Simon's boat began to sink. He fell to Jesus' feet and begged him to go because Simon was a sinful man. Jesus told Simon to get up as now he was a fisher of men.
Paul was converted one day while on the road to Damascus. He was tired and unsuspecting when suddenly a bright light shone all around him. The others that were with him could hear all that was said but could not see anything during that time. Saul fell to his knees and saw the face of Jesus Christ talking to him. Jesus asked him why Saul persecuted him and from that moment he became a believer. Jesus told him to stand up but when he did, he could not see.
Meanwhile, in Damascus, an angel appeared to Annanias, a dedicated christian. The angel said that there was a man called Saul who was an atheist but was blind. The angel then told Annanias to go and heal this man of his blindness. Saul was blind for three days until Annias healed him. Saul immediately changed his name to Paul.
Simon was called Cephas by Jesus which means Peter when he was called to be a disciple.