Differentiate between on-page and off-page optimisation ?

Unlike on page optimization, off page SEO depends on another web page to improve your site rankings. Off-page optimization mainly deals with link building. It's an ongoing process and requires obtaining new links that are given priority by search engines.

On-page SEO refers to factors on your own website that you can optimize such as the underlying code and the content.
Off-page SEO refers to actions taken to affect your site's trustworthiness and authority by building the right inbound links and social signals.

On page is optimizing the website seo friendly.
Off page is creating quality backlinks to the website.

On page and Off page are the two types of seo. In on page we have need to login the website to changing in the website this on page seo changes the layout of your website. such as in on page we change the keywords, images size, meta tags, content(quality and quantity), And off  page is the type of seo that we do to make backlinks of our website. We paste our website's link on other high da  pa sites to increase the da pa of our site and increase traffic also.

On page seo refers to the process that is followed on the website itself. Some of the tasks involved are:

Keyword research
Meta tags and title
Meta description
Robots.txt file
Sitemap generation
Content development
Image optimization

Off page refers to the link building and promotion of your website in search engines. Some of the most effective off page activities are:

Guest posting
Article submission
Press release submission
Social bookmarks
Classified ads
Infographics submission