Learn to program C, with the world's most popular language, using your Raspberry Pi. The C programming language been used to program everything from the tiny microcontrollers used in watches and toasters up to huge software systems - most of Linux (and Raspbian itself) is written in it. Learn to code with C is the perfect introduction to the language and is easy to follow with your Raspberry Pi (or any other hardware format).
This book is unsurprisingly entry-level, but it has great presentation, and reasonably thorough explanations. Of course, it's very short, so there are restrictions on how much it can really delve into each topic, but every explanation is certainly robust enough.
This book will not teach you how to code with C, but it's a good introduction to the topic, and is particularly good at explaining the fundamental parts of C that are weird to people living in the 21st Century. Pointers, for example - and finnicky memory management things in general.
Also, this book is published by Raspberry Pi press, but a Raspberry Pi is not required to work through the exercises. I have never used a Raspberry Pi, and I got through all of the exercises just fine. The screenshots are all from a Raspberry Pi, but the author uses Geany for text editing, and that looks pretty much the same on all platforms.