Some were passed along to me, others I bought at a thrift store or garage sale and most were bought specifically to sell on Amazon for more money. I have a few books I will sell, but many of these others are not worth much, so it's time to donate them.
I do not see the point in keeping some of these books if I am not referencing or using any of these books. I have books that I reread and refer to, like my herb and holistic medicine books, so I am keeping those. Also, I have music biographies, fiction by favorite authors, great science fiction, fun Star Wars novels and some great photography books. (Music related). Most of the music related, biographies and herbal medicine books were given to me as gifts.
I can appreciate a great fiction novel, but I have a huge preference for non-fiction. I am a sucker for metaphysics, books on health, music biographies and some comics. I used to read Dragonlance novels and lots of science fiction when I was younger. I own a few classics that I love and sometimes reread. However, there are a few novels that I have read and probably will never read again, so it's time to let them go. The same goes for cookbooks. I went through a phase where I was buying nothing but cookbooks or my mom and I would trade off a few. Being a librarian, I use the library on a regular basis and stay up-to-date on current releases. I do not feel the need to buy every book that is on the bestseller list or all the books that Oprah raves about. (Although Oprah has some great picks sometimes!). People donate to the library all the time and there are some great titles and some that I know are dated but had some high value at one time. I have let go of all types of books in the past seven years and I am ready to share my collection with others that may be interested. If I haven't read it in the past ten years, why am I holding onto them?