Using eval()

[James Birkett]

Could anyone explain how I could use this in terms of parsing PHP on my forum?
I have tried using php.net to understand the syntax of it but I just cannot grasp it.
Thanks in advance.

[Dismounted]

$foo = "echo 'Hello World!';"
eval($foo); // prints Hello World!
As you can see, usage of this can be VERY VERY DANGEROUS and as such, it is generally discouraged to use this function (apart from the performance issues).