How can I enable keep-alive?

I ran a Google Page Speed and it says I scored 57/100 because I need to "Enable Keep-Alive" and "Enable Compression". I did some Google searches but I can't find anything. I even contacted my domain provider and asked them to turn it on, but they said it was already on.

Long story short:

1.) What is Keep-Alive?

2.) How do I enable it?

Solution

Keep-alive is using the same tcp connection for HTTP conversation instead of opening new one with each new request. You basically need to set HTTP header in your HTTP response

Connection: Keep-Alive