GuRu – Gu – in Sanskrit means – darkness or ignorance, Ru – removal, break, shatter. Therefore, a Guru is one who shatters the veil of ignorance by imparting true knowledge.
Acharya Is a spiritual teacher who teaches, guides, by himself practicing what he preaches and in the process removing the sishya’s (students) ignorance.
Parampara refers to the lineage of spiritual teachers who continuously impart knowledge to their disciples in an unbroken succession.
In Vaishnava sampradaya Sriman Narayana - the Paramathma is the supreme knowledgeable one. He is the Swatantran – independent of anyone – Seshi, all the others dependent on him – Paratantras – Sesha – Jeevathma.
Paramathma is the 11th nama in Sri Vishnu Sahasranamam – Parasara Bhattar explains in Bhagavath Guna Dharpanam Sriman Narayana is the supreme being, Master of himself. Adi Sankara explains Paramathma as the supreme being with supreme knowledge, who is distinct from the Jeevathmas and with no attachment or desires.
In Bhagavad Gita Chapter 13, Verse 23 Lord Krishna himself says
upadraṣhṭānumantā cha bhartā bhoktā maheśhvaraḥ
paramātmeti chāpy ukto dehe ’smin puruṣhaḥ paraḥ
उपद्रष्टानुमन्ता च भर्ता भोक्ता महेश्वर: |
परमात्मेति चाप्युक्तो देहेऽस्मिन्पुरुष: पर: ||
The supreme Bhagavan resides within the body as Athma – Inner Soul (Antharyami) and witnesses, permits, supports, controls and enjoys the person and his actions. He is Transcendental Controller – THE PARAMATHMA.
Hence in Sri Vaishnava Sampradaya Sriman Narayana who is eternal, omniscient, omnipotent and one who knows everything a sarvagnan is the Prathama (first) Acharya and from HIM starts the OrAN Vazhi Sri Vaishnava Parampara meaning a single one to one transfer of knowledge. He takes this position out his own volition. That Sriman Narayana imparts the knowledge to PirAtti (Sri Mahalakshmi thayar) his consort who is a part of him and is never separated from him. PirAtti out her abundant karuna and Vaatsalyam transfers that knowledge to the descendants reaching us in this Bhoolokam.
Our Acharya Parampara. Starts with Periya perumal and Piratti and comes down to our present day Acharyas.
1. Sriman Narayana – Paramapadhanathan
2. Sri Mahalakshmi thayar
3. Vishwaksenar - Senai Mudhaliar
4. Nammazhwar
5. Nathamunigal
6. Uyyakkondar
7. Manakkal Nambi
8. Yamuna Muni - Alavandhar
9. Periya Nambi
10. Ramanujar, Emperumanar, Bhashyakarar
Acharya lineage after Swami Bhagavad Ramanujar in the Sri Vaishnava sampradayas subdivides into Vadakalai and Thenkalai Sampradaya
1. Sri Brahma Tantra Svatantra Parakala Math - 1360
2. Sri Ahobila Math – 1398
3. Srirangam Srimad Andavan Ashramam
4. Sri Poundarikapuram Andavan Ashramam
Acharyas from some leaned families who are direct descendants of Bhagavath Ramanaja’s appointed direct 74 sishyas. They do not follow any of the maths or families like Mudalianadan, Koyil kandhadai etc. Some well-known Swayamacharyas are Prathivadhi Bhayankaram, Gomata Kulathar, Thathacharya, Thirumala Anandham pillai, Nallan Chakravarthi.