As the web has evolved, more data is sent from the server to the client and from the client to the server. HTTP 1.1 does not compress header fields. HTTP works over TCP and a request is sent over this connection, where the headers are large and contain redundant data. TCP works on Slow Start implemented by a network congestion-avoidance algorithm, which places packets over the network. If the headers are compressed, more packets can be sent over the wire. HTTP/2 fixed this problem with header compression, which takes advantage of TCP, resulting in a faster transfer speed of data.