Swift Algorithms & Data Structures is a book originally written in Objective-C. The goal was to practice standard programming techniques for technical interviews. At the time, it was considered to expand the project to other languages such as Java and Python. However, with the introduction of Swift, the language provided the perfect blend of concise syntax and modern language features. Fast forward to the present, the series has been used by thousands of developers to prepare for technical interviews in over 70 countries.