Hope you notice the difference tomorrow night. Everyone gains sleep Tuesday night June 30, 2015. Here's why.

 

Tomorrow you wil gain a full second of sleep during the last minute of Tuesday, June 30. The hour will contain 61 seconds instead of the usual 60.

Atomic clocks around the world will coordinate the leap second, which is necessary to keep Coordinated Universal Time (UTC) — the system that guides most international civil times systems — synced with the Earth's rotation.

On Tuesday, atomic clocks should read 23:59:59, then 23:59:60, before switching over to Wednesday with 00:00:00.

According to MASHABLE.COM,  NASA has everything you need to understand why there is a time adjustment in this video.

I know I will take full advantage of the "extra sleep".