Added snippet for getDifferenceInSeconds

snippets/getDifferenceInSeconds.md

@@ -0,0 +1,15 @@
+---
+title: getDifferenceInSeconds
+tags: dates,beginner
+---
+
+Returns the diffrence in seconds between 2 supplied dates.
+
+```js
+const getDifferenceInSeconds = (start, end) =>
+  (end.getTime() - start.getTime()) / 1000;
+```
+
+```js
+getDifferenceInSeconds(new Date('2020-12-24 00:00:15'), new Date('2020-12-24 00:00:17')); // 2
+```