Form, database and dysplay.. HELP!

[Anon]

OK I have a form in my page, and all the information in included in my database. When I read one of the information and I display him on a page, all the "internet format character" is generated.... OK I MEAN:

(The project is like a message board)
If the guy right in the subject box:

"<B> Hello World!"

All the text will be in BOLD.. but I don't want the <B> to be generated.. I have try to print with "print", "printf", and echo but nothing work...

What should I do .. ?

[Anon]

try:

eregi_replace("Hello World", "<b>Hello World</b>", $str);

[Anon]

If I use the replace function I will have to replace EVERY html tag that exist and that would be really bad. Since my output is in a string there must be a way to avoid parsing html?