If no word equivalent to the concepts of Tibetan Buddhism, literature is not lacking but it falls into two through. The extension does not reflect the specificities of French words that make their Tibetan counterpart evil; other texts use transliterations of the original but leave the reader puzzled even when they are explained (too) briefly.
Rare are the authors who have sufficient knowledge of both Tibetan culture and Western culture to present satisfactory Tibetan Buddhism. Hence the need for additional equipment.
Encyclopaedia of Buddhism Cornu is excellent for all forms of Buddhism but by his erudition is even daunting for the beginner.
This book focuses on the key concepts. Each entry is independent of the others but pique the interest so you can get across the book by following its own interests. Some entries are accompanied by quotes for the more advanced player. Finally color illustrations nicely complement the ensemble.
The book is published by "Clear Light", a publisher specializing in Tibetan Buddhism, which was already a guarantee of seriousness. An index could have helped save a few seconds during the search of a term.
Lack locate an entry for Tibetan Buddhism in all of Buddhism, and the explanation of the difference between Theravada and Mahayana. But to stay within the limit of 70 pages, he probably had to make choices. Or, this difference is explained in another entry. I have not yet read the whole book.