Add Yahoo as a preferred source to see more of our stories on Google. The number zero was a relatively recent and crucial addition − it allows numbers to extend in both directions forever.

One subway ride in NYC costs $3. Gizmodo has been around for 24 years. The Sun is just one of some several hundred billion stars in the Milky Way, which is also just one of some trillions of galaxies ...

Here’s a game: Ask a friend to give you any number and you’ll return one that’s bigger. Just add “1” to whatever number they come up with and you’re sure to win. The reason is that numbers go on ...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com. Why don’t numbers end? – Reyhane, age 7, Tehran, ...