I have just installed Apache web server on my computer. I have managed to use it locally (I can open index.php from my computer using my web browser). But I would like to make my web site available publicly. I found out that for that I need to open port 80. I started to do it and now I have to specify to which protocol I need to apply these rules (TCP or UDP). Can anybody, pleas, help me?
TCP establishes a connection and UPD just sends packets.
You will have packet loss with UDP. Sites like youtube.com use UDP for video streaming because it doesn't matter if you miss a few frames. youtube.com uses UDP because it's faster than TCP because that connection isn't established and you probably wouldn't notice missing frames anyway.
You want to use TCP because you don't want packet loss.