Introduction
User Datagram Protocol or UDP is a simple protocol. This protocol is unreliable - when a data packet is sent, it cannot be not known if it will reach its destination or not. There is no acknowledgement, retransmission, or timeout. When multiple data is sent at once, the order which they arrive cannot be predicted. They might be out of order. The data that is sent with sequence 1,2,3 might be recieved as 2,3,1. So, sending files through UDP socket is a bit difficult.