The Computer Science Book
The Computer Science Book
A complete introduction to computer science in one book
About the Book
Learning computer science is difficult. Things are even tougher if you’re learning by yourself. This book is trying to change that.
When I started my first real programming job, fresh from a bootcamp, I was crushingly aware of how little I knew. Worse than that, I was constantly reminded of how much I didn’t even realise that I didn’t know. Well-meaning colleagues would casually mention some concept or convention that I’d simply never heard of.
The obvious thing to do is to study computer science. But how do you study computer science if a four year degree isn’t an option? Where should you start? How do you chart your way through the whole of computer science, studying topics in the right order? Which of the many classic textbooks should you read?
After years of study, I’ve written a book that will make computer science easy. Ten concise chapters covering each of the major areas will give you a comprehensive introduction to the fundamentals and guide you towards the best resources for further study. We’ll cover everything you need to be an effective developer. You’ll understand how everything fits together, be confident of what you know and, even more importantly, be aware of what you don’t know. Each chapter functions as both a standalone introduction and a primer for further, independent study.
Reader Testimonials

Adrian Booth
This book is an essential read for anyone who felt they missed out on a computer science education, but also is a great reference guide for graduates. Tom distils each topic beautifully and succinctly, making it an overall joy to read where you're provided just enough information on a topic to leave you craving more. It's choc full of references to guide you in exploring each topic in more detail and contains many visual aids which assist you along the way

John Whiles
I read this book to get an overview of computer science. I'm a working programmer, but I lacked some of the knowledge that would help me progress in my career. This book covers the topics I lacked confidence in. I now feel like I can understand discussions about topics like algorithmic complexity, compilers, networking and more. If I need to go deeper, I now have a solid base to work from. I’ve been able to apply some of the content to my day to day work
Table of Contents
- Introduction
-
Theory of computation
- Introduction
- Automata theory
- Computability
- Algorithmic complexity
- Conclusion
- Further reading
-
Algorithms and data structures
- Introduction
- Data structures
- Abstract data types
- Algorithms
- Conclusion
- Further reading
-
Computer architecture
- Introduction
- Representing information
- Circuits and computation
- The processor
- Memory
- Performance optimisations
- Conclusion
- Further reading
-
Operating systems
- Introduction
- Common operating systems
- The boot process
- Interrupts: hardware support for software
- The kernel
- Managing the processor
- Managing memory
- Managing persistence
- Conclusion
- Further reading
-
Networking
- Introduction
- What is a network?
- The networking stack model
- The Internet Protocol
- Transmission Control Protocol
- Internet addressing and DNS
- The web, hypertext and HTTP
- Conclusion
- Further reading
-
Concurrent programming
- Introduction
- Concurrency, parallelism and asynchrony
- Determinacy and state
- Threads and locks
- JavaScript and the event loop
- Communicating sequential processes in Go
- Conclusion
- Further reading
-
Distributed systems
- Introduction
- Why we need distributed systems
- A theoretical model
- Handling network partitions: the CAP theorem
- Consistency models
- Consistency protocols
- Conclusion
- Further reading
-
Programming languages
- Introduction
- Defining a programming language
- Programming language concepts
- Programming paradigms
- Type systems
- Conclusion
- Further reading
-
Databases
- Introduction
- What does a database offer?
- Relational algebra and SQL
- Database architecture
- B-trees
- Indexes
- Concurrency control in SQLite and Postgres
- Conclusion
- Further reading
-
Compilers
- Introduction
- Compilation and interpretation
- The program life-cycle
- Building a compiler
- Who to trust?
- Conclusion
- Further reading
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