Javacript lets me make fancy ui elements (such as the tabs on my comics I've read page*.

it also make it easier to upkeep my site long term as footers and some nav bars use javascript, it means i can edit on or two files and that change applies to multiple pages

that also means that if you have javascript turned off it will also break a lot of the navigation bars/link, best alternative I have is using the Sitemap

ps i got the base code more making those tabs from W3Schools