Keurigs are universal coffee machines for home and office use. They prepare single servings of coffee. More than 60 brands produce K-Cups that can be used with Keurigs, so you can brew 400 types of drinks. Keurig machines can prepare hot and cold coffee, tea, hot chocolate, and more. You can even buy a reusable filter and brew a drink with your own ground coffee. The larger the number of models, though, the more difficult it is to make a choice. How can you choose a coffee machine from more than 50 models? We've put together in-depth reviews and instructions to help you choose, and keep you satisfied with, a Keurig coffee maker.