Racket and Scheme Language References

• Racket home page
• The Scheme Programming Language (Dybvig)
• An Introduction to Scheme and its Implementation
• The Racket Guide
• An introductory programming book based on Scheme
• Schemers.org

C Language References

• The C Programming Language by Kernighan and Ritchie. Alas, not free, but one of the best books ever written describing a programming language.
• The C Book
• C Tutorial
• C Programming
• Programming in C
• Valgrind documentation
• Makefile tutorial

Git References

• Pro Git
• Git Immersion
• Easy Version Control with Git