in my linux firewall i can setup allowed TCP and UDP ports. I want to allow port 7778 which is port on which my web control panel is running. So i want to ask what is difference between TCP and UDP and how to know which one is example 7778 port, 80 port, 22 port?

Update: netstat is the linux tool that can list open ports. Example this way i check if port 2087 is open and see whether its TCP or UDP:

netstat -tlnp | grep 2087
tcp 0 0* LISTEN 211393/cpsrvd (SSL)