Barnes & Noble offers two different Nooks, and Amazon has four different Kindles -- not to mention readers from makers like Kobo and Sony. And there are tablets that offer electronic books, too.
"You can read e-books on a tablet, but a dedicated e-book reader is lighter, easier to hold in one hand, has a longer battery life and crisper type," said Paul Reynolds with Consumer Reports. "All of those will make a difference in hour after hour of reading."
Among its tests, Consumer Reports assessed how fast each reader can turn a page. Some are really fast, while others are slower.
Another test looked at how easy they are to read in different lighting. The best e-readers have no trouble with bright light, making them good for reading outside. If you're going to be reading in the dark, a reader with a built-in light is a real plus.
"While there are other manufacturers, your choice probably boils down to a Nook or a Kindle. Those are the brands with the best combination of performance, price, and features," said Reynolds.
At the top of the ratings is the $119 Barnes & Noble Nook Simple Touch with Glowlight. The page turns are quick, and it has crisp, readable type as well as a built-in light.
For much less, consider the $69 Kindle with Special Offers from Amazon. It also rated excellent for readability. However, the page turns aren't quite as fast.
Consumer Reports says there's something else to factor in when deciding which e-book reader to buy: If someone in your family already has a Kindle or a Nook, it might make sense to get the same kind, that way you can share their library and avoid paying for the same book twice.