Here is a list of 10 affordable books that can help you master various programming language

"Python Crash Course" by Eric Matthes (Python)

"Eloquent JavaScript" by Marijn Haverbeke (JavaScript)

"Head First Java" by Kathy Sierra and Bert Bates (Java)

"Learn Python the Hard Way" by Zed A. Shaw (Python)

"C Programming Absolute Beginner's Guide" by Perry and Miller (C)

"Automate the Boring Stuff with Python" by Al Sweigart (Python)

"JavaScript: The Good Parts" by Douglas Crockford (JavaScript)

"Ruby on Rails Tutorial" by Michael Hartl (Ruby)

"SQL Performance Explained" by Markus Winand (SQL)

"Learning PHP, MySQL & JavaScript" by Robin Nixon (PHP, MySQL, JavaScript)