Hooray, welcome to the fun that is GO.
A little more about the Tauros, some Pokémon that appear have a higher CP level, and therefore are harder to catch. There are certain items like Razz Berries and stronger Poké Balls (Great Balls, Ultra Balls) you can use to increase your chance of catching it next time it pops up. You can find those at Pokéstops once you level up a bit more.