Sri Vaishnavam is a universal religion, which is open to one and all. Follower of Lord Sri Vishnu are called Vaishnavas. When they worship Maha Vishnu along with Maha Lakshmi (Sri) they are called as SriVaishnavas.
Sri Vaishnavas worship Sriman NarAyaNa in five forms viz. param , VyUham , Vibhavam , antharyAmi and ArchA
Param/ Parama padham : Lord Sriman NarAyaNa in “Amardha Thirukolam” on Adisesha along with His consorts in Sri Vaikuntam as “para VaasudEvan” enjoying the Saama ghAnam along with Nithyasoorigal (Ananthan, Garudan, Visvaksenan…) and Mukthathmakkal. (soul of a person who has done saranagadhi and got mukkthi).
Vyuham : Lord Sriman NarAyaNa is in “Sayana Thirukolam” on the Adhisesha in the Thirupparkadal (Milk Ocean) as “KshIrAbhdhi nAthan” in His “yOga NidhrA”. Here DevAs and maharishis can have dharshan.
Vibhavam : Lord Sriman NarAyaNa took many incarnation in this world such as Maccha, Koorma, Varaaga, Narasima, Vamana, Parasurama, Rama, Balarama, Krishna etc., with some avathAra Kaaryam. Can be enjoyed by His contemporaries.
AntharyAmi :Lord Sriman NarAyaNa resides within all of us as our soul by giving guidance day to day to people who care to listen to Him. Through the difficult JNa~na Yogam, one can visualize His svarUpam in our heart.
Archa: Lord Sriman NarAyaNa gives Darshan to all of us in various temples on this earth in the form of Idol. In these temples all the Bakthas like us can have his dharshan and enjoy every day.
AzhwArs who were immersed in kalyANa guNAs of Emperumaan Sriman NarayaNan. They are 12 AzhwArs worshiped Sriman NarayaNan in the above mentioned five forms. They have composed the Naalaayira Divya Prabhandham which is the vEdAs in Tamil to make all of us understand.