This list should tell you everything you need to know.
Edit:
In all seriousness, you should do a little research on your own. However, if you can wait until then, I have a blog post scheduled for Tuesday that talks about exactly this topic.
Hi Rajesh,
Don't think there'll ever be a real complete list with the constant changes in the web. But important on page factors I tend to focus on includes
Title tag
H1 tag
Keyword tag
Meta Description tag
internal linking structure
