13 Sects in Chinese Mahayana:
1. Chu-she tsung / Kosa Sect in Sanskrit, originated from Abhidharma School or Realistic School in India
2. Cheng-shih tsung / Satyasiddhi Sect in Sanskrit
3. Lu tsung / Vinaya Sect in Sanskrit
4. Chan tsung / Dhayna Sect in Sanskrit / Zen in Japan, sometimes it is called Meditation School, or simply The School
5. Ching-tu tsung / Sukhavati Sect in Sanskrit / Pure Land Sect, sometimes it is called Amidism
6. Hus-yen tsung / Avatamsaka Sect in Sanskrit / Flower Adornment Sect
7. Tien-tai tsung / Heavenly Platform Sect
8. Fa-hsien tsung / Dharmalaksana Sect in Sanskrit / Mere-consciousness Sect / Hosso in Japan, originated from Yogachara School in India
9. San-lun tsung / Three Shastra Sect / Sanron in Japan, originated from Madhyamika School in India
10. Chen-yen tsung or Mi tsung / Esoteric School / Mantrayana or Tantrayana in Sanskrit / Word of Truth Sect / Shingon in Japan
11. Ti-lun tsung
12. Nirvana Sect
13. She-lun tsung
Although there are 13 schools, but the more common ones are the Chan (Zen) school, Pure Land school, and Mi Tsung - which is Vajrayana. Vajrayana is more frequently found in Tibet, but smaller numbers of Vajrayana practitioners can be found in Japanese Buddhism, and their sect is called Shingon. The Esoteric School is also a Mahayana school.
