Delivering is where everything the assets needed to show a page is called, and the whole page design is shown in the program. Now and again, it might happen that a specific asset may postpone the delivering of pages
Contents that defer Page Rendering
What prompts the expansion in the heap time?
We should see how a program shows a page.
Simply run the URL of your site through Google's PageSpeed Insights device. You may likewise utilize designer instruments in your program by squeezing the F12 key. Go to the System tab, invigorate the page. All the assets will be recorded in the request for delivery.
Check the below image difference between the 3 modes of script execution
3)presence of the ‘async’ attribute executes the script asynchronously with the page render.