you had 4 questions in that post. 1 and 2 are the last two questions in ur big paragraph.
1) You will have to learn new codes, but there is not too much of it. Once you get the general syntax, the functions that exist are logical. The syntax is very simple.
<?php
functionname(parameters,moreparameters);
//This is a comment, dont forget about semicolons
$variable="variable text" . $textfromothervariableaddedon;
?>
Lotsa tutorials out there on syntax and basic stuff.
2) There is no need to retye your existing sites; the html will work perfectly. The only change you need for the php scripts to work is change the file from a .html to a .php. just like you have open and close tags (example: <html></html>) the open and close tags for php are <? and ?>. The code can go anywhere on the page.
3) The advantage to php is to make the page dynamic and much easier to update. you can also make it interactive by having a member log in, etc. if you use php, and your front page is, for example, about the news in Pefkakia, it wud be easy. since news is added every day, you can use a php script that makes a new page (with forms) where you can just type in what you want, the php will take the text and automatically insert it into the website. also, you can use it to get times and password protect stuff etc. when you get REALLY advanced, you can even make games with it.
4) How it works: i hope ur familiar with the terms client and server. if not,
Client = person going to the website
Server = server that the website is hosted on
Client requests the website from the server. the server checks to see if there is any php script to execute. since php is a server script, it will execute anything that is in the php tags. because of this, it is impossible for the client to see what you have in ur php script (unless they are |-|4><><0R5 [hackers]). the server runs the script and outputs the proper html content which is then sent back to the client. its pretty handy
i would suggest
www.w3schools.com to begin learning, thats where i started.
i hope this helped, please give me reputation points
