Here are some of the best books for a beginner – very good introductions to the basic ideas of Buddhist thought, taking the common subset between Theravada, Mahayana and other schools.
A good first book, by Richard Gethin.
The Foundations of Buddhism_Gethin_1998
And here’s another classic by Dr Rahula Walpole
What the Buddha Taught_Walpole
And here’s one by Paul Williams
Guru Soul 
You've decided to leave a comment. Awesome! Please keep in mind that comments are moderated and only the relevant ones will appear on the blog after a while. So, let's have a meaningful discussion and thanks for dropping by!