MISH! has her stars and all, but I'm more cut-and-dried about how I rate books. My three categories are as follows:
Buy: This book proved worthy of many rereads and a desire for it to always be close at hand. Deserving of the fund spendage. Definitely a book I'd talk up to a friend.
Borrow: While I wouldn't necessarily drop cash on this for my personal library, I enjoyed it enough/found it interesting enough to suggest others borrow it from friends or from the library, because I liked it, and might reread it some other time, or if I get a particular craving for this type of book.
Bypass: Would avoid this book like the Plague, either due to poor writing, plotting, or other thing that would make me want to throw it across the room in frustration. I'm here to help you spot these rotters.
If, for some reason, I forget to state at the review's end how I rate a book, check the links under the posts. I've probably still managed to add the appropriate tag.
I take a traditional approach to rating books, using a five-star system. My interpretation:
1 star (★)
Since giving 0 or negative stars isn't to my taste, 1 star generally means I didn't like it or there was something I found very disturbing about it.
2 stars (★★)
Below par. Not terrible, but not something I'd recommend, either.
3 stars (★★★)
Average. Not my taste but not bad. Some books are just "okay."
3 1/2 stars (★★★1/2)
Good/above average. A lot of books fall in this realm, where I enjoyed them but aren't quite 4-star quality.
4 stars (★★★★)
Really good. Often bordering on great, but not to the point where I'd deem it a favorite.
5 stars (★★★★★)
Excellent. Amazing. Incredible. Powerful. Or sometimes I just enjoy a book so much I can't do anything but give it 5 stars.