On Page SEO you attract readers by providing high quality content. The technique is to make the articles as relevant as possible to what the searcher is looking for. It greatly helps if you are an expert on the topic you are writing about. On page is process of defining keyword, Meta tags, content duplication, domain, title etc. which have to follow while developing site.
Off page is process of effort that we take in marketing our i.e. bringing maximum follower to site using marketing technique 1)blog post 2)forum posting 3) classified 4)article posting, 5)social bookmarking.