Two schools of Shaivism in North India.

Monistic Saivism developed in the North in two schools, one being the Trymbaka School which flourished in Kashmir (the Medhapitha) and is known at present as the Kashmir Saivism, and the other being the school named Ardha Tryambaka which developed in the Kangra area called Jalandharapitha. Many systems of practical Sadhana (spiritual discipline), e.g. Vama, Daksina, Koula, Mata, Trika, etc., were prevalent among the followers of Saivism. The Trika system of Sadhana was highly popular with the Saivaites of Kashmir. Abhinavagupta, the greatest among the authors of the Trika system, had picked up the highest form of the Kaul system of practice from his most esteemed preceptor, Sambhunatha, the presiding teacher of the Ardha Trymbaka School. Kaulism also became sufficiently popular with the practitioners of Trika system in Kashmir since then.

http://koausa.org/koshursamachar/sahibkaul.html

This Jose Pereira identifies seven Saiva Schools by a clear schema. 
These seven schools are each represented by a black trident arranged in 
a cluster. 'Standing erect at the center of the cluster beneath the 
yoga flame - is Trika, greatest of all the schools. 
The other six tridents are linked in pairs on either side of the center. The first 
pair, adjacent to the Triadic trident, in this order, consists of the 
two rival saiva siddhanta schools - the Southern or Devotional 
Orthodoxy (dravida) and the Northern or Gnostic Orthodoxy (gauda). The 
next set consists of the newest of the schools - the Hero-Saivism 
(vira-saiva) of Basava and the Saiva Nondualism (sivadvaita) of 
Srikantha. Lastly, there is the Dualist Pastoralism (pasupata) of 
uncertain foundation and the Monist Pastoralism (lakulisapasupata) of 
Lakulisa. The white tridents at the periphery of the cluster represent 
the Logicism (nyaya) of Gautama and the Atomism (vaisesika) of Kanada. 
They began as Saiva schools but were later demythologized.
Although the black trident schools are more or less distinct, they all 
have three basic ideas in common: Master, Beast and Bond. It is on this 
triad that Saiva Orthodoxy is built.'