Well, even in a server-side PHP app, you have some client-side stuff for better interactivity and a smoother experience. Custom elements let you encapsulate thi

Well, even in a server-side PHP app, you have some client-side stuff for better interactivity and a smoother experience. Custom elements let you encapsulate this stuff. It's really not necessary, but if you want to reuse or redistribute them, they are pretty nice and self-contained (mostly).