Javascript - inline vs external script - what's the difference?

Question

I have a few snippets of javascript scattered about my pages - many are contained in my own .js files, however some of the stuff that I\'ve found online sits directly on the

Answer 1

There is little difference in using one or the other way. The real difference comes from the advantages/disadvantages that each one has.

Inline scripts

• Are loaded in the same page so is not necessary to trigger another request.
• Are executed immediately.
• The async and defer attributes have no effect
• Can be helpful when you are using a server-side dynamic rendering.

External scripts

• Gives better separation of concerns and maintainability.
• The async and defer attributes have effect so if this attributes are present the script will change the default behavior. This is not possible with inline scripts.
• Once a external script is downloaded the browser store it in the cache so if another page reference it no additional download is required.
• Can be used to load client code on demand and reduce overall download time and size.