You get a page in the internet to inform yourself about the changes since your last visit.
You had to study the page to this in all details till now. With the WebAssistant parts added newly can be highlighted in color. You can be perceive so the changes more specifically.
Unfortunately, less interesting content are frequently exchanged on many pages. Therefore it is often useful to remove these changes by a advertising blocker. You can prevent the download of unwanted content with Surf Set/Filter/Advertising.