"The Wheel" consists of booklets issued in a format 4.8 x 7.2 inches, typically ranging from 40 to 80 pages. Since the inception of BPS in 1958 about 250 titles have been published, though not all have been maintained in print. The booklets cover a wide range of topics and can be categorized as: Introductory Booklets; Specific Teachings (on the main topics of Buddhist doctrine, such as the Four Noble Truths, the Noble Eightfold Path, Dependent Origination, the three marks of existence, kamma and rebirth, and so forth); Meditation and Mind Training; Dhamma Reflections (more personal explorations of the relevance of Buddhist principles for spiritual understanding and practice); Philosophy and Psychology; Faith and Devotion; Monastic Life; Comparative Studies; Buddhist History and Culture; Buddhism and the World Today; Translations from the Pali Canon; Non-Canonical Buddhist Literature. All Wheel Publications have been digitalised and are being reissued in bound volumes as well as put on the BPS website.