What's the best way to add scripts to all pages?

If you need to add multiple script embeds that need to be loaded on every page on the site (e.g. Google Analytics, External Video Service, Adobe DTM, etc.), what's the best way to do this?



the word script got removed from title
[edited by: sonofagum at 9:17 PM (GMT 0) on Thu, Aug 6 2020]