There are so many great books on yoga out there and I would like to share my favourites with you. I generally think that you should learn yoga from a teacher in person but books can be a great way to get some additional information. Moreover finding a yoga school where you can learn asana is quite easy but finding someone who can teach you the philosophy part can be rather difficult - so it is very handy to fall back on books.
Also svadhyaya (self study = studying the ancient texts but also study your own self) is mentioned as one of the niyamas (recommended activities and habits for healthy living, spiritual enlightenment and liberated state of existence) in ashtanga yoga - so reading and studying books is a part of the yoga journey.
The Art of Vinyasa
by Richard Freeman and Mary Taylor
An amazing book on ashtanga yoga asana as a form of meditation in motion. Every asana comes with an explanation of form, alignment, anatomy and with and great photos. The authors share their holistic approach on yoga. I highly recommend this book for beginners and advanced practicioners alike.
The Mirror of Yoga
by Richard Freeman
Richard Freeman gives an amazing and comprehensible overview of the many teachings, practices, and scriptures that serve as the basis for all the different kinds of yoga—hatha, bhakti, jnana, karma, tantra, and others.
The Mirror of Yoga
The Yoga Sutras of Patanjali
Since this text was written down earlier than 400 CE there are many translations and interpretations of this classic. The yoga sutras consist of 196 sutras (aphorisms) organized into 4 padas (chapters). I recommend to read several different interpretations and also crossread them and make up your own mind.
Theses are two translations/interpretations I really liked:
Das Yogasutra: Von der Erkenntnis zur Befreiung (this one is only available in german unfortunately)
The Yoga Sutras of Patanjali: Commentary on the Raja Yoga Sutras by Sri Swami Satchidananda
A Yogis roadmap
by Bhavani Silvia Maki
A very personal and aproachable interpretation of the Yoga Sutras and the yogic path in general.
A Yogis roadmap
The Bhagavad Gita
by Eknath Easwaran
That is the most know Story out of the epic "The Mahabarata" about Arjuna and his charioteer Lord Krishna. There are also countless translations and comments on this text. I really liked the one by Eknath Easwaran.
Samadhi: The Great Freedom
by Gregor Maehle
After taking part in one of his Workshops I started reading this book and it was eye opening on so many levels.
Samadhi: The Great Freedom
I hope you find theses books helpful and if you have any book recommendations for me just post them in the comments below.