Can i change the text on a random website?

i was looking at these guys computers once of school and there where changing the website itself. Like the text and everything. They wouldn't tell me how though. I looked in the address bar and it started out with ';Java Script.'; I just want to know how I could do that!Can i change the text on a random website?
Firebug, a Firefox extension.



http://getfirebug.com/Can i change the text on a random website?
They were using scripts but you can also try doing the following.

Download firefox if you havent already, then download a plugin called ';firebug';. Restart firefox and right click on the text/image you wan to change in any website, then select ';inspect element'; option. Firebug will show you the code and allow you to edit it. This is specially used by webdesigners so that they don't have to save and refresh their site just to see how something might look a certain way or another.
That's Java programing, to do that you'll need to learn how to write code in Java. To do that on a random website is malicious hacking and you'll find your self in a lot of trouble by doing that. Even if you're a minor, you still get in a lot of trouble and your parents can be liable economically for the damages you do on a website.



Picture this:

1- You get nailed.

2- There comes court.

3- Legal fees.

4- Lawsuits.

5- Your parents lose the house, cars and banks accounts as part of a settlement.



You're not only destroying your life but the life of your entire family just for a little trill, ignorance of the law don't makes you less guilty, just more stupid in the eyes of a judge.
For Mozilla, if you go into Internet Options, then under Content you can change the size and font, if you un-check ';Allow websites to use their own...'; all the websites you visit should be viewed with your settings.
I'd have to say it would be Firebug - Firefox extension. But it's not permanent. Just allows you to adjust it temporarily.