Why do you conjugate English verbs with "to" in front of them?

I mean the infinitive forms: to be, to work, to play, etc. I think it's related to their Old English forms, but I'm not sure. Do you know any web page that answers this question?

2012-03-13T13:48:46Z

Yes John, what I'd like to know is its origin.

John2012-03-13T13:43:40Z

You answer your own question. When you need to use the infinitive form you put 'to' in front of the word. As in Spanish you'd put 'ar', 'er' or 'ir' at the end. Are you more asking what the origin of that form is?