President Obama marked National High Five Day by posting a picture of himself high-fiving Vice-President Biden. Perfectly acceptable if they actually had something to celebrate, but if they posed for this picture then that would be a breach of high-five ettiquette. That said, here is your essential guide to high-fiving do's and don'ts:

1, Be sure the other party wants to high-five you as much as you want to high-five them. There's nothing worse than being left hanging.

2. Never ask to high-five anyone. It makes you look desperate and needy.

3. Don't be the "high-five" guy randomly high-fiving everyone within sight at the bar.

4. Don't high-five at a Nazi rally.

5. Don't start too soon because you're likely just to get a wave back and then you'll feel awkward wondering if you should leave your hand up or not.

6. Don't high-five at funerals and urinals.

7. Beward of the old "Ball and Socket" when you attempt a high-five and your partner goes for the fist bump.

8. Accuracy counts. If you miss and end up with a "High-Two" keep on walking like you didn't even know them. Non-acknowledgement is the key.