Data Encryption

Hi, I'm not sure if this is even a PHP question, but I'm hoping someone can help me. I need to encipher data to be stored in a database and then I need to be able to decipher it to use it. I was thinking of using DES and I obtained a pair of keys, but I'm not sure where to go from there. I've scoured the internet for help, but I just can't figure out which is the best way to do what I need to do. If someone could please point me in the right direction I'd really appreciate it. Once data is sent in a form, how do I encipher it before saving it in the database and then how do I decipher it to be used later on? Also, not to sound helpless, but I'm pretty new to PHP and I don't quite have a handle on the jargon, so if it could be explained as simply as possible that would be helpful. Thanks so much! Cat