I've been making a website with about 25 pages and every time I want to update the nav bar, or the footer, I have to go through every page and make the change!
Surely there is a way to have the header and the footer (and the side bar!) in separate documents and call them in the same way a CSS is called so they don't have to be repeated on every page.
Bonus: Is this likely to affect SEO in any way? Might it slow down the site?
Thank you,
Tara