I am very interested in this...I have heard much about it....

So what is it really, where can i get it, and how can i get tutorials/lessons if they exist

Hex editors open files and display their contents to you at the byte (or even bit) level, usually in hexadecimal. If you're working with some non-compressed data, you can use hex editors to change the values of single bytes and see what sort of change that results in, which tells you what information those bytes contained. Or you might already know and be making changes intentionally, whichever. I use XVI32 because it's free and functional and people like it. All you should really need is a knowledge of what ASCII and Hexadecimal are, and the rest will more or less come down to figuring out what bytes you want to edit and to what and why.

What Unknown Rabbit said. I use WinHex myself, as it supports files larger than 2GB without gobbling up all the memory in my computer.

You can delete the password of jj2 levels (.j2l) with it. (idk if this message will be deleted)

I personally use Hex Workshop and WinHex.

When I find myself needing to use a hex editor (which isn't as often these days, regrettably), I like to use WinHex. It's fairly easy to pick up, and it seems to not be as much of a system tanker (resource hog) as the rest of the tools out there.

XVI32 is a good tool for hex editing.

Originally Posted by Hunter

It won't, there was a whole thread about password removing.

But I used it to many levels and it works

Originally Posted by SHÁKÉR NL

You can delete the password of jj2 levels (.j2l) with it. (idk if this message will be deleted)

Removing passwords by hex editing is actually quite a bit harder than you may imagine. The easy part is blanking the password.

okay then

Originally Posted by Ricerind

Removing passwords by hex editing is actually quite a bit harder than you may imagine. The easy part is blanking the password.

Or you just use TECjcs

TECJCS is for pussies.

Originally Posted by cooba

TECJCS is for pussies.

well this is for people who don't know how to blank the pass from lvl's with hex.
Well and to completly remove the pass from a lvl is very hard..I think :-?

Originally Posted by DarkB

Well and to completly remove the pass from a lvl is very hard..I think :-?

I never said it was difficult. Just difficult to do with a hex editor.

It's quite easy. Just blank it, then follow these instructions.
http://www.jazz2online.com/jcf/showthread.php?t=16776

http://www.youtube.com/watch?v=MLRayJkJUCQ&fmt=18
And now you can enter every .j2l file with JCS

It's sufficient to nullify the first three bytes of the password field. The fourth byte is used as a flag for home cooked levels, and modifying it does not affect the password. An interesting thing happens when you set those three bytes to 0x00BABE. I used this trick to make a nifty application.

Originally Posted by Cpp

It's sufficient to nullify the first three bytes of the password field. The fourth byte is used as a flag for home cooked levels, and modifying it does not affect the password. An interesting thing happens when you set those three bytes to 0x00BABE. I used this trick to make a nifty application.

yes that thing works.

Ha. That's an interesting program. But can't it be just as easily opened again by reclearing the password?

It can, assuming you know how. People who don't will be left wondering.
It's an experimental program, not some new reliable way to protect your levels.