What is the difference between synchronous and asynchronous page rendering ?, Synchronous asynchronous page rendering

What is the difference between synchronous and asynchronous page rendering ?, Synchronous asynchronous page rendering

Synchronization: the browser accesses the website. The browser creates a new tabpage, a new memory block, loads all the resources of the page, and renders all the resources. However, as long as there is any operation on the page, it will render all the requests from the new beginning, and the browser will control the http.

Asynchronous: Use the previously rendered page data, and do not need to re-render the page for interaction data with the background to partially update the page. Control http by yourself.