making a simple guestbook

If you have an html and you sumbit it to a basic PHP file receiver, I wonder how you make them add up. how do you make the submitted forms stack instead of each submission replacing the other? I have no clue where to even start looking for an answer.

wrap print statements and make wrap element an array? do i need file I/O for this so the messages get stored somewhere?

PHP is a very confusing jungle for me at the moment. Note that I haven't gotten to the database part of php in my course yet.

many thanks in advance

You could store data in files like @Col. Shrapnel has answered.

However, if you are going to create a guestbook that also will be used online, I would recommend learning to work with databases. It would be good practice.

A database helps you to organize your data in a logical manner.

Of course you will need file I/O to store messages.
Otherwise how they are supposed to be saved? So, you have to save your messages in a file.

To add new data at the bottom of the file you have to append it instead of rewriting.

if you're using file_put_contents function, use it with FILE_APPEND flag:

file_put_contents($file, $data, FILE_APPEND);

if you're using fopen(), use 'a' mode instead of 'w'

If you want to store data between submissions, you can store in is the _SESSION variable, just call session_start at the beginning of your program. Messages can be stored in a file, for example. You can use sqlite as a database if you wish.

What do you mean by wrapping?