Merge pull request #3942 from shaedrich/spa

Add topic "Spa"

Author: zkoppert

topics/spa/index.md

@@ -0,0 +1,10 @@
+---
+display_name: Single-page application (SPA)
+short_description: Single-page applications are client-side applications that combine the logic for different contents into one page.
+topic: spa
+related: mpa, vuejs, reactjs, svelte, astro, angular, emberjs, javascript, routing, pushstate
+wikipedia_url: https://en.wikipedia.org/wiki/Single-page_application
+---
+**Single-page applications** (**SPA**) are client-side applications that don't route via different pages but rather combine the logic for different contents into one page. This was historically achieved via hashbang URI fragments (`#!`). With the introduction of the [`pushState` API](https://developer.mozilla.org/en-US/docs/Web/API/History/pushState), this state can now be properly used within the browser history, in bookmarks and sharing.
+
+Another important point for SPA was the lack of proper [SEO](https://github.com/topics/seo) but developers and frameworks found ways around that.