Add Generate A V4 UUID In The Browser as a JavaScript TIL

javascript/generate-a-v4-uuid-in-the-browser.md

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+# Generate A V4 UUID In The Browser
+
+The [Web Crypto
+API](https://developer.mozilla.org/en-US/docs/Web/API/Web_Crypto_API) provides
+a
+[`randomUUID`](https://developer.mozilla.org/en-US/docs/Web/API/Crypto/randomUUID)
+function for generating v4 UUID values which are cryptographically random.
+
+It works like this:
+
+```javascript
+> crypto.randomUUID()
+'f2050c5e-af52-4ca2-b4d6-23758b3396c9'
+> crypto.randomUUID()
+'079d5186-84d4-41d6-a660-edafb6a74c86'
+```
+
+No two UUIDs will be the same. This is a great way to generate IDs that are
+guaranteed to be unique. Or if you need a value that is practically impossible
+to guess.
+
+I was surprised to see that as of writing this, this function has great browser
+support. Modern versions of all browsers except Internet Explorer have
+implemented `randomUUID`.