List of free available programming books From stackoverflow

Meta-Lists

25 Free Computer Science Ebooks
Book Training - On Video!
Cheat Sheets (Free)
CodePlex List of Free E-Books
Free Tech Books
Galileo Computing (German)
How to Design Programs: An Introduction to Computing and Programming
Microsoft Press: Free E-Books
MindView Inc
O'Reilly's Open Books Project
Sofware Program Managers Network - Free EBooks
TechBooksForFree.com
Theassayer.org
Wikibooks: Programming

Graphics Programming

DirectX manual (draft)
Learning Modern 3D Graphics Programming (draft)
GPU Gems
GPU Gems 2 -
ch 8,14,18,29,30 as pdf
GPU Gems 3
Graphics Programming Black Book
ShaderX series

Language Agnostic

97 Things Every Programmer Should Know
Algorithms and Data-Structures (PDF)
Algorithms (draft)
The Architecture of Open Source Applications
The Art of Unix Programming
Best Kept Secrets of Peer Code Review
Binary Trees
The Cathedral and the Bazaar
Clever Algorithms
Communicating Sequential Processes (PDF) - Tony Hoare
Compiler Construction (PDF)
Computer Musings (lectures by Donald Knuth)
Data Structures and Algorithms: Annotated Reference with Examples
Database Fundamentals (PDF)
Data-Intensive Text Processing with MapReduce (PDF)
The Definitive Guide to Building Code Quality
Developers Developers Developers Developers (broken download link?)
Digital Signal Processing For Engineers and Scientists
Domain Driven Design Quickly
Don't Just Roll the Dice
Essential Skills for Agile Development
Flow based Programming
Foundations of Computer Science - Al Aho and Jeff Ullman
Foundations of Programming
Getting Real
Getting started with Open source development (PDF)
The Great Tree List Recursion Problem
Guide to the Software Engineering Body of Knowledge
How Computers Work
How to Design Programs
How to Think Like a Computer Scientist

How to Write Parallel Programs
How to write Unmaintainable Code
I Am a Bug
An Introduction to the Theory of Computation
Introduction to Functional Programming (class lectures and slides)
Introduction to Information Retrieval
Is Parallel Programming Hard, And, If So, What Can You Do About It?
Learn to Program
Let's Build a Compiler
Linkers and loaders
Linked List Basics
Linked List Problems
Mathematical Logic - an Introduction (PDF)
Matters Computational
Mining of Massive Datasets
NASA Manager Handbook for Software Development (PDF)
NASA Software Measurement Handbook
Object-Oriented Reengineering Patterns
Online Course Materials
OO Design
Operating Systems and Middleware (PDF and LaTeX)
Patterns and Practices: Application Architecture Guide 2.0
Patterns of Software: Tales from the Software Community (PDF)
Planning Algorithms
PNG: The Definitive Guide
Pointers And Memory
Producing Open Source Software
Programming Languages: Application and Interpretation
Programming Methodology
Project Oberon (PDF)
Security Engineering
Structure and Interpretation of Computer Programs
Summary of the GoF Design Patterns
The Little Book of Semaphores
The TCP/IP Guide
Think Stats: Probability and Statistics for Programmers (PDF, code written in Python)
Type Theory and Functional Programming
Understanding IP Addressing: Everything you ever wanted to know (PDF)

ASP.NET MVC

NerdDinner Walkthrough

Assembly Language

ProgrammingGroundUp (PDF)
Paul Carter's Tutorial on x86 Assembly
Software optimization resources by Agner Fog

Bash

Advanced Bash-Scripting Guide
Lhunath's Bash Guide

C / C++

Beej's Guide to Network Programming
The C book
C++ Annotations
C++ GUI Programming With Qt 3
CS106X Programming Abstractions in C++
Essential C
Introduction to Design Patterns in C++ with Qt 4 (PDF)
Learn C the hard way
Matters Computational: Ideas, Algorithms, Source Code, by Jorg Arndt
The new C standard - an annotated reference
Object Oriented Programming in C (PDF)
Software optimization resources by Agner Fog
Thinking in C++, Second Edition
Also see: The Definitive C++ Book Guide and List

C#

See .NET below

Clojure

Clojure Programming
Clojure - Functional Programming for the JVM

CoffeeScript

Smooth CoffeeScript
The Little Book on CoffeeScript

ColdFusion

CFML In 100 Minutes

DB2

Getting started with DB2 Express-C (PDF)
Getting started with IBM Data Studio for DB2 (PDF)
Getting started with IBM DB2 development (PDF)

Delphi / Pascal

Essential Pascal Version 1 and 2
The Tomes of Delphi

Django

Djangobook.com

Emacs

GNU Emacs Manual, 16th Edition, v. 22
An Introduction to Programming in Emacs Lisp, 3rd Edition

Erlang

Learn You Some Erlang For Great Good

Flex

Getting started with Adobe Flex (PDF)

F#

The F# Survival Guide
F Sharp Programming in Wikibooks
Real World Functional Programming (MSDN Chapters)

Forth

Starting Forth
Thinking Forth

Git

Pro Git
The Git Community Book
Git From The Bottom Up (PDF)

Go

The Go Tutorial

Grails

Getting Start with Grails

Haskell

Learn You a Haskell
Real World Haskell

HTML / CSS

Dive Into HTML5
HTML Dog Tutorials

Java

Java Application Development on Linux by Carl Albing and Michael Schwarz(PDF)
How to Think Like a Computer Scientist
Java 6 Tutorial (PDF)
Java Thin-Client Programming
Sun's Java Tutorials
Thinking in Java
OSGi in Practice (PDF)

JavaScript

Crockford's JavaScript
Eloquent JavaScript
Essential Javascript & jQuery Design Patterns for Beginners
JavaScript Essentials
jQuery Fundamentals (starts with JavaScript basics)
Mozilla Developer Network's JavaScript Guide

JavaScript (Node.js specific)

Up and Running with Node
The Node Beginner Book
Mastering Node.js

Latex

The Not So Short Introduction to LATEX (perfect for beginners)

Linux

Advanced Linux Programming
GNU Autoconf, Automake and Libtool
GTK+/Gnome Application Development
The Linux Development Platform (PDF)
The Linux Kernel Module Programming Guide
Secure Programming for Linux and Unix

Lisp

ANSI Common Lisp
Common Lisp the Language, 2nd Edition
Common Lisp: A Gentle Introduction to Symbolic Computation - David S. Touretzky
Common Lisp Quick Reference
Let Over Lambda - 50 Years of Lisp
Natural Language Processing in Lisp
On Lisp
Practical Common Lisp
Successful Lisp: How to Understand and Use Common Lisp - David Lamkins
Sketchy LISP - Nils Holm

Lua

Programming In Lua (for v5 but still largely relevant)
Lua Programming Gems (not entirely free, but has a lot of free chapters and accompanying code)

Mathematica

Mathematica® programming: an advanced introduction by Leonid Shifrin

Maven

Better Builds with Maven
Maven by Example
Maven: The Complete Reference
Repository Management with Nexus
Developing with Eclipse and Maven

Mercurial

Mercurial: The Definitive Guide
HGInit - Mercurial Tutorial by Joel Spolsky

Nemerle

See .NET below

.NET (C# / VB / Nemerle / Visual Studio)

C# Essentials
C# Programming - Wikibook
C# Yellow Book (intro to programming)
Charles Petzold's .NET Book Zero
Data Structures and Algorithms with Object-Oriented Design Patterns in C#
Entity Framework
Illustrated C# 2008 (.zip, dead link)
Nemerle
O'Reilly's C# Pocket Reference Manual (dead
link)
Programmer's Heaven C# School Book (covers C# 1.0 and 2.0)
Threading in C#
Visual Basic Essentials
Visual Studio Tips and Tricks (VS 2003-2005 only)

NoSQL

CouchDB: The Definitive Guide
The Little MongoDB Book

Oberon

Programming in Oberon (PDF)

Objective-C

The Objective-C Programming Language

OCaml

Introduction to Objective Caml (PDF)
Objective Caml for Scientists
Unix System Programming in OCaml

Oracle Server

Oracle's Guides and Manuals

Oracle PL/SQL

PL/SQL Language Reference
PL/SQL Packages and Types Reference
Steven Feuerstein's PL/SQL Obsession - Videos and Presentations

Parrot / Perl 6

Using Perl 6 (work in progress)

Perl

Beginning Perl
Embedding Perl in HTML with Mason
Essential Perl
Extreme Perl
Higher-Order Perl
The Mason Book
Modern Perl 5
Perl & LWP
Perl for the Web
Perl Free Online EBooks (meta-list)
Perl The Hard Way
Practical mod_perl
Web Client Programming with Perl

PHP

PHP Essentials
Practical PHP Programming (wiki containing O'Reilly's
PHP In a Nutshell)
Symfony2
Zend Framework: Survive the Deep End

PowerShell

Mastering PowerShell

Prolog

Adventure in Prolog
Applications of Prolog
Building Expert Systems in Prolog
Introduction to Prolog for Mathematicians
Learn Prolog Now!
Logic, Programming and Prolog (2ed)
Natural Language Processing in Prolog
Natural Language Processing Techniques in Prolog
Prolog Programming A First Course
Prolog Techniques
Simply Logical
Visual Prolog 7.2 for Tyros

PostgreSQL

Practical PostgreSQL

Python

Building Skills in Python Version 2.5
Byte of Python
Data Structures and Algorithms in Python
Dive into Python
Dive into Python 3
The Django Book
How to Think Like a Computer Scientist: Learning with Python
Invent Your Own Computer Games With Python
Learn Python The Hard Way
Natural Language Processing with Python
Python Bibliotheca
Python for Fun
Snake Wrangling For Kids
Think Python (PDF)
Thinking in Python

R

The R Manuals
The R Language
R by example
Computational Statistics, Jeremy Penzer

Ruby

Learn Ruby the hard way
MacRuby: The Definitive Guide
Mr. Neighborly's Humble Little Ruby Book
Programming Ruby
Ruby Best Practices
Why's (Poignant) Guide to Ruby (mirror)

Ruby on Rails

Ruby on Rails Tutorial: Learn Rails By Example

Scala

Exploring Lift (published earlier as "The Definitive Guide to Lift",
PDF)
Lift (Github)
Pro Scala: Monadic Design Patterns for the Web
Programming in Scala, First Edition
Programming Scala
Scala By Example (PDF)
A Scala Tutorial for Java programmers (PDF)
Xtrace (Github)

Scheme

Concrete Abstractions: An Introduction to Computer Science Using Scheme
The Scheme Programming Language (Edition 3)
The Scheme Programming Language (Edition 4)
Simply Scheme: Introducing Computer Science

Sed

Sed - An Introduction and Tutorial

Smalltalk

Dynamic Web Development with Seaside
Free Online Smalltalk Books (meta-list)
Squeak By Example (Smalltalk IDE)

Subversion

Subversion Version Control (PDF)
Version Control with Subversion

SQL (implementation agnostic)

Developing Time-Oriented Database Applications in SQL
Use The Index, Luke! (a guide to SQL database performance for developers)
Learn SQL The Hard Way

Teradata

Teradata Books

Vim

A Byte of Vim
Vim Recipes

Websphere

Getting started with WebSphere (PDF)