Adding User Authentication in PHP

[Freptratpiorp]

Now I know that I should not try to reinvent the wheel and try to write an authentication system, since I don't understand the security issues well enough. However, I need to add a basic authentication system to my site, so I can limit access to certain resources.How do you recommend that I do this?Edit: I am not trying to make an authentication system myself. I'm looking for libraries that I can use to integrate authentication in my website.