8080 Port : Why do we use port 8080 for http in some webservers?

Why do we use port 8080 for http in some webservers? Port 80 vs 8080 vs 443: What's the Difference? localhost:8080 - Web Server and Application Port Guide Port 8080: Understanding Its Role and Common Uses in... Port 8080 (tcp/udp) :: SpeedGuide .