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A random free book:Information Retrieval


The Assayer is the web's largest catalog of books whose authors have made them available for free. Users can also submit reviews. The site has been around since 2000, and is a particularly good place to find free books about math, science, and computers. If you're looking for old books that have fallen into the public domain, you're more likely to find what you want at Project Gutenberg.

You can browse the catalog by clicking on a link in the bar above. You need to become a member if you want to post your own reviews, add books to the database, or participate in discussions of books. Click here to become a member. Membership is free, and the only personal information you need to give is your e-mail address. (We won't spam you, and other visitors will only be able to see your address if you say it's OK.)

Members can also reply to each other's reviews, creating a discussion of a book, and can choose to receive e-mail notifications when new discussion has occurred about a particular book.

Click on the Help link above for more detailed information on the purpose of The Assayer and how to use it.

UC Davis Group to Create Free Texts

The LA Times reports that a group at UC Davis, led by chemistry professor Delmar Larsen, has an ambitious plan to produce half a dozen free and open-source wiki-based math and science textbooks.

September 2, 2014

California Open Educational Resources Council Starts Up

Two years ago, the California state legislature passed two bills to fund the development of 50 free college textbooks by 2013. The faculty council for the initiative now has a web page. The initial goal was clearly not realistic, and has now been downsized and delayed.

September 2, 2014

Brown Signs California Bill for Free Textbooks

California Governor Jerry Brown has signed SB 1052 and 1053, authored by state senator Darrell Steinberg, to create free textbooks for 50 core lower-division college courses.

SB 1052 creates a California Open Education Resources Council, made up of faculty from the UC, Cal State, and community college systems. The council is supposed to pick 50 core courses. They are then to establish a "competitive request-for-proposal process in which faculty members, publishers, and other interested parties would apply for funds to produce, in 2013, 50 high-quality, affordable, digital open source textbooks and related materials, meeting specified requirements." The bill doesn't become operative unless the legislature funds it -- a questionable prospect in California's current political situation. The books could be either newly produced (which seems unlikely, given the 1-year time frame stated) or existing ones that the state would buy or have free access to. Unlike former Gov. Schwarzenegger's failed K-12 free textbook program, this one specifically defines what it means by "open source," rather than using the term as a feel-good phrase; books have to be under a CC-BY (or CC-BY-SA?) license, in XML format. They're supposed to be modularized and conform to state and W3C accessibility guidelines. Faculty would not be required to use the free books.

September 28, 2012

Apple Taking the Proprietary Road with eBooks?

Today Apple announced easy-to-use software for creating electronic textbooks. Picking through the typically overblown Apple hype, there are some disturbing signs that Apple may be heading down the same road that Amazon has taken by trying to make books proprietary and only availale from a single distributor. Previously, Apple had hitched its wagon to the open Epub standard as the format for its electronic books, whereas Amazon uses their own format. Apparently they are now using a format that is similar to, but not the same as Epub 3: "Books are not technically in the EPUB format, but they borrow from it (likely EPUB 3). Certain interactive elements of the books require the files to be done in the slightly different iBooks format, Apple says." No word on interoperability. Embrace and extend, anyone? They have also announced that some titles, including E.O. Wilson's Life on Earth, will only be available electronically from them. This is the same ugly lock-in tactic that Amazon has already been trying to pull. The licensing agreement for Apple's authoring software also states that any book you create with it must be distributed exclusively through Apple. It appears that B&N may be the only remaining ebook publisher that is committed to open formats and nonexclusive distribution.

January 19, 2012

California State Senator Pushes for Free Textbooks

Although former Governor Schwarzenegger's free digital textbook initiative for K-12 education was a failure, state senator Darrell Steinberg has a new idea for the state-subsidized publication of college textbooks. (Details are given in the PDF files linked to from the bottom of the page.) Newspaper editorials seem positive.[1], [2].

January 4, 2012

B&N Stands up to Amazon on Lock-In

Amazon has been trying to negotiate exclusive deals with publishers to sell e-books; obviously their dream is to achieve lock-in, so that their customers become their captives. Barnes and Noble is responding by refusing to sell paper books by publishers, such as DC Comics, who won't let them sell the electronic version.

October 9, 2011

Illegal Fees for Disappearing Books

Publishers such as Pearson have been illegally charging California community college students for required access to online books, which the students can no longer access once the semester is over. A task force, packed with industry representatives, met behind closed doors and recommended changing the law.

September 10, 2011

Michael Hart, 1947-2011

Project Gutenberg founder and electronic book pioneer Michael Hart has died of a heart attack. He started his life's work by typing the U.S. Declaration of Independence into a computer in 1971 and making it available for free downloading.

September 6, 2011


NSF has funded a grant, with Jason Grout at Drake as PI, for a project called UTMOST: Undergraduate Teaching in Mathematics with Open Software and Textbooks. The idea is to take preexisting free math textbooks and convert them into worksheets for the open-source math program Sage. Students can then use a computer aided algebra system to try calculations on the same screen from which they're reading the book itself.

June 7, 2011

Results of Textbook Initiative Announced

The results of California Governor Schwarzenegger's Free Digital Textbook Initiative were announced today at a symposium near Los Angeles, which I attended. Participants included open-source types from Curriki, CK-12, and Connexions, as well as teachers, politicians, IT folks, hardware vendors, and textbook publishers. Sixteen free high school math and science textbooks were submitted, and were evaluated as to whether they met state content standards. Almost all the books were Creative Commons-licensed works produced by individuals and nonprofits, with the exception of a consumable biology workbook from Pearson.

The genesis of Schwarzenegger's initiative was the current state budget crisis, so it was entertaining to see the various interests jockeying for a bigger slice of a shrinking pie. Dell and Apple would like to see funds for textbooks freed up so that they can be used to buy computers on which students can access the free books, and they had demos with actual grade school kids (highly intent on their Apple laptops) and high school kids (chewing gum and socializing in front of their Dell netbooks).

The traditional publishers didn't seem to be able to decide how to present themselves. Pearson's rep referred to its workbook as "free and open-source" (it's not open-source). Houghton Mifflin Harcourt's rep, when questioned about DRM, said that her company was committed to DRM, and envisioned its DRM'd materials being mixed and matched with open-source ones. Both said that they wanted to be service providers (think Red Hat), rather than just content providers (a la Microsoft) -- but, hey, they produce really great content, too. Apple and Dell's reps argued for open formats such as XML.

Nobody seemed sure about the implications of the settlement in the Williams case, which requires equal access to books for all students. Will poor students be locked out because they don't have computers? Schwarzenegger's proposed solution is to print out books as needed, but Murugan Pal from CK-12 pointed out that current state law allows a school to use textbook funds to pay $80 for a book from a commercial publisher, but forbids it to pay $10 to print out a copy of a free book at Kinko's.

As a community college professor, I was surprised by the level of top-down control that seems to be taken for granted in the K-12 system. There was a lot of concern about whether a digital textbook that had been blessed by the state would then change overnight, falling from its state of grace. CLRN, which is running the evaluation process, says that they want authors to freeze their books for two years after the evaluation. This seems to run counter to the Governor's criticism of traditional textbooks as "antiquated." Pal from CK-12 pointed out that although CK-12 is a wiki, it's not open for editing by all, like Wikipedia. But teacher Lainie Rowell recounted the charming story of the Lousiana students who found out that there was no Wikipedia article about the Pitot House, and proceeded to write one as a class.

A big change since I went to high school in California is that many high schools are offering online classes, and over-scheduled, affluent students seem to love being able to fit them in between soccer and SAT prep classes. Orange Country Superintendent of Schools William Habermehl proposed that since budget cuts will force schools to put 42 students in an Algebra 1 class, they could have 30 kids (the ones who need more help) in the classroom, and the other 12 taking the class online. Somehow this sounds to me like making the teacher teach two classes for the price of one, and as a parent I'm a little worried about what it would be like if one of my daughters was in the group of 12 deemed not to need any help.

August 11, 2009

New York Times on Electronic Textbooks

The New York Times has a good article on electronic textbooks, including the California initiative.

August 8, 2009

California Initiative for Free Textbooks

Motivated by the California state budget crisis, Governor Schwarzenegger has announced a Free Digital Textbook Initiative, which is producing a list of free, online high school math and science textbooks that are aligned with state content standards. The list will be announced June 16, and the intention is to have the books used in classrooms in fall 2009. The idea seems to be to look for preexisting free books put out by individuals. This article has some useful background, but it mistakenly suggests that the arduous state adoption process will be an obstacle to the FDTI; statewide adoption only applies to K-8, but FDTI is doing high-school books. There was a previous, unsuccessful effort called COSTP, which tried to produce a history textbook using Wikibooks. Here is a BBC article about the present effort, and here is a newspaper opinion piece by the Governor. This is a transcript of a speech by the Governor, with some interesting Q&A at the end. Twenty books were submitted (press release, links). The four books from traditional publisher Pearson are consumable workbooks, not actual textbooks.

June 16, 2009

Flat World Knowledge

Flat World Knowledge is a new startup company that is distributing CC-BY-NC-licensed textbooks via free digital downloads and print on demand. Professors can produce customized versions of the texts by, e.g., cutting chapters they don't intend to cover, and can edit "down to the sentence level." They're currently at the testing stage, and plan a full commercial launch in 2009. There doesn't seem to be any information on their site about what books they've got lined up. The restriction to the CC-BY-NC license seems unfortunate to me, since it locks out a whole body of books that are licensed under CC-BY, or under licenses like the GFDL (used, e.g., by Wikipedia) that are compatible with CC-BY.

April 25, 2008

Open Text Book

Open Text Book is a new web site that catalogs textbooks that are free-as-in-speech.

October 4, 2007


Manybooks is a web site for free books, as well as shorter works. They seem to have started by converting the books on the Project Gutenberg DVD into a variety of convenient formats. In addition, they have a pretty good catalog of science fiction novels and short stories whose authors have made them free online.

September 15, 2007


Scribd is a new service that aims to do for the print medium what youtube did for video. It could be a useful no-cost, no-hassle way for authors of free books to distribute them online, without having to maintain their own web sites. Books are automatically translated into a variety of formats, and by default users are shown a flash interface that lets them flip through the book page by page. My own experience with Mac/Linux/Firefox was that the flash interface didn't work very well, but YMMV, and I'm sure the glitches will get worked out over time.

August 11, 2007

Ink Textbooks

Ink Textbooks is a new textbook publisher that plans to sell books inexpensively in print, and also make the same books available for free online in digital form. They require an exclusive license from the author, so their system isn't compatible with Creative Commons or GFDL-licensed books.

July 28, 2007

Free Curricula Center

The Free Curricula Center is a new project that is going to try to get people to cooperate on writing free textbooks.

Mar. 23, 2006

An Infrastructure for Free Books

Here is an article I wrote about what's going on these days in the world of free books. From the article: With the cost of college textbooks up 62% over the last decade, pressure is building for an alternative model of publishing: the free book. Five years ago, an author had to be very persistent --- maybe even a little crazy --- to try the new approach. But now a whole new infrastructure is springing up to make it easier.

Dec. 15, 2005

1000 Free Books

The Assayer's catalog has now passed the milestone of 1000 free books.

Dec. 12, 2005

A Proposal For Governnment-Financed Textbooks

The Center for Economic and Policy Research has published a proposal for the government to finance the production of textbooks, on the condition that they would then be placed into the public domain. Personally, it raises my libertarian hackles, but it's true that one of my favorite physics textbooks, PSSC Physics, was created as a government-financed project.

June 22, 2005

CALPIRG Cheaper Textbooks Campaign

Lindsay Hopkins (lindsay dot hopkins at gmail dot com) contacted me today about the CALPIRG Cheaper Textbooks Campaign, of which she's the statewide coordinator. CALPIRG, the California Public Interest Research Group, is an organization of students in the University of California System. Their Cheaper Textbooks Campaign is interested in putting together a how-to manual on writing your own free textbook.

Apr. 21, 2005

Free Textbook Project

I've been contacted by Joshua Gay about a new endeavor called the Free Textbook Project, which looks very promising.

Apr. 8, 2005

Real Names Now Required

I've been seeing an increasing number of "reviews" that are actually the author's promotional blurb. These are usually painfully obvious, and I delete them immediately. However, I've decided to start requiring new users to supply their real names when they set up an account. Of course, there's nothing to stop them from faking this information. When you read a review, think critically about whether the reviewer appears trustworthy. It's usually a sign of trouble if the reviewer has only ever written a single review on The Assayer, and the review reads like promotional material.

Dec. 16, 2004

3000th Member

The Assayer's membership passed the 3k mark with member jameslee. Thanks, everybody, for all of your continuing contributions to The Assayer!

Aug. 10, 2004

No New Non-Free Books

When I first created The Assayer, I decided as an afterthought to allow people to review non-free books here. I didn't want to come off as a fire-breathing zealout, and I thought an exclusionary policy toward non-free books might cause a lot of arguments about what qualified as free. Since then, the site's catalog of free books has grown greatly, and gradually more and more of them are getting reviewed by TA members. It's become clear to me, however, that accepting reviews of non-free books is not producing anything worthwhile ( is the venue for that), and is taking up a lot of my time and resources. In particular, there have been a lot of cases where the authors of a non-free book posted thinly veiled promotional material in the guise of a review. I've also noticed that at least one person has cross-posted reviews here and on, despite the prominent warnings on this site not to do that because Amazon owns the copyrights on reviews submitted to them. That creates a potential for legal problems that I don't need. Therefore I've decided to stop accepting new reviews of non-free books. Reviews of non-free books that are already in the database will be retained, except in cases where they appear to violate Amazon's copyright. (Note added Oct. 2005: It appears that no longer claims copyright on reviews, but only a royalty-free license to use them.)

Feb. 15, 2004

New Subject Categories

The number of books in Library of Congress category QA, math and computer science, is getting huge, so I've introduced smaller subcategories, which you'll see when you browse by subject. I've done my best to place as many math and computer books as possible in appropriate subcategories, but some of them get pretty esoteric, so feel free to help out if you have the necessary expertise; to place a book in a subcategory, just click on its "edit information about this book" link, and it will show you the legal choices.

Jan. 11, 2004

Warning Messages Eliminated

I didn't receive any more comments about the warning messages (see below). I've decided to eliminate them.

Nov. 8, 2003

Comments on Warning Messages?

I recently added a feature to The Assayer that some might consider a bug :-) When you're viewing a review, you get an error message if the reviewer hasn't supplied a real name, hasn't supplied a bio, or has only every written one review. One user of the Assayer has e-mailed me to say he hates the warnings. Does anyone else have comments? The warnings are meant to handle a situation that is unfortunately pretty common: the author of a book submits a review of his own book. Am I overreacting? Let me know! Click on the contact link above for info on how to e-mail me, and please let me know if it's OK to quote you and use your name in this space. Based on the one user's feedback, I've already made the warnings less prominent.

Two Licenses Eliminated

I've decided that it was a bad idea to create two of my own homebrewed licenses for reviews, and I will no longer be accepting new reviews under these licenses. I think the proliferation of licenses is a bad thing, and I'm also not a lawyer, so I don't know if these licenses have legal defects.

The default license for reviews is still the OPL without options A and B. This may seem strange, since its creator, Dave Wiley, recommends using a Creative Commons license for new works instead of the OPL. However, it seems to me that the OPL is more appropriate for book reviews, because it requires modified versions to be given out with a description of the modifications, which is important in order to keep people from changing a reviewer's words to misrepresent the reviewer's opinions.

Aug. 29, 2003

OpenContent Shuts Down

Dave Wiley, a pioneer in the application of copyleft licenses to non-software publications, is now recommending that people use Creative Commons licenses instead of the Open Publication licenses (OPL). The site will remain up, and still has the text of the Open Publication licenses.

Open E-Book Format Proposed

Here are some links discussing a recent proposal for an open format for e-books: [1], [2], [3], [4].

Jun. 5, 2003

GFDL not free?

There's been some discussion about whether the GFDL license actually fails to qualify as a true free-information license.

Apr. 24, 2003

Internet Book List

Internet Book List is a new site for user-submitted book reviews. It's been discussed on Slashdot.

Mar. 7, 2003

Books as Sewage?

Arnold Kling has an article with a skeptical take on the idea of free-information publishing. It's been discussed on Slashdot.

Jan. 15, 2003

An Article About Free Books

Here's an article I wrote about what's new in the world of free books. It was recently discussed on Slashdot.

Oct. 21, 2002

1000th Member Joins The Assayer

The Assayer's membership moved into four-digit territory. Go team!

May 3, 2002

Green Tea Press

It used to be that if you made a list of publishers who understood free information, there was only one: O'Reilly. That's changed a little, e.g., Addison-Wesley has print-published Programming Ruby, which is also free in digital form. But even so, any addition to this short list is newsworthy. Green Tea Press is a new print publishing house started up by Lisa Cutler and Allen Downey, one of the authors of How to Think Like a Computer Scientist, a wonderful book which also happens to be free in digital form. It's good to see an initiative like this coming from an author, and it will be interesting to see if the digitization of the publishing industry leads to a more author-centered approach. Best wishes go out to Lisa and Allen in their new endeavor!

Feb. 11, 2002

New Licenses For Reviews

Based on requests from users, I've added two more options for the licenses of reviews: a BSD-style license called the Free Word license, and another called the Soapbox license, which is intended for use with writing that expresses opinions, in order to ensure that it can't be modified so as to misrepresent the opinions of the original author. Both of these are homebrewed licenses. The Free Word is really nothing but the BSD license, with a couple of minor changes to adapt it to writing that isn't software. The Soapbox license is my attempt to address reviewers' concerns, without going as far as a verbatim-copying-only license, which I think would be inappropriate for a free-information site like The Assayer.

Feb. 1, 2002

TA's Most Prolific New Member

The Assayer has a prolific new reviewer! Check out the eclectic work of voiceofthewhirlwind, with reviews on topics from history to crime fiction to technology.

Jan. 18, 2002

More Choices of Licenses?

A TA user e-mailed me recently to suggest adding a third license to the menu you choose from when submitting a review. His concern was that both the GFDL and the OPL allow modification, which might allow people to make it sound as though you said things you didn't. Although both licenses require changes to be documented, the concern is a valid one, since TA deals with opinion, not software documentation, which is what GFDL in particular is tuned up for. Would it be a good thing to have a third choice, basically saying that the review can be copied but not modified? If you have comments, please e-mail them to me at crowell02 at, and I'll post them on TA.

B. Crowell, Jan. 18, 2002

User Lucas Walter says "I was going to suggest the same thing, maybe add OPL _with_ option A (minor alterations permitted, but no semantic changes)."

Jan. 18, 2002

Another possibility, for those who prefer it, is a BSD-style license of some kind. IMHO this is more free than GPL-style licenses such as the GFDL and OPL-without-options, although "freer" isn't necessarily the same as better :-)

B. Crowell, Jan. 18, 2002

The Assayer Featured in Indian Newspaper

The Assayer was prominently featured in a recent article in the Indian newspaper The Hindu. A big thank you goes out to reporter J. Murali!

July 19, 2001.

The contents of this web page, except the parts contributed by members of The Assayer, are copyright (c) 2000 by Benjamin Crowell, and are copyleft licensed under the Open Publication License 1.0, without options A or B.