The Indian Territorial Army (TA) is a second line of defence after the Regular Indian Army; it is not a profession, occupation or a source of employment. It is only meant for those people who are already in mainstay civilian professions; in fact, gainful employment or self-employment in a civil profession is a prerequisite for joining the Territorial Army. Volunteers of the Territorial Army usually serve in uniform for a few days every year, so that they can bear arms for national defence in times of dire need or national emergencies.
The modern Territorial Army was inaugurated by the first Indian Governor-General of India, C. Rajagopalachari, on 9 October 1949 after the Independence Territorial Army Act was passed in 1948. The annual Prime Minister's Territorial Army Day Parade takes place on 9 October.
The Territorial Army initially had various types of units such as armoured regiments, infantry battalions, air defence, medical regiments, engineers field park companies, signal regiments, Electrical and Mechanical Engineers (EME) workshops, coast batteries, Army Service Corps GT Coy, ASC Compo Pl, and AMC field ambulances. By 1972 these units were either disbanded or converted to Regular Army units with the exception of infantry battalions.
Territorial Army units were actively involved in military operations in 1962, 1965 and 1971. The "Terriers" have also taken part in Operation Pawan in Sri Lanka, Operation Rakshak in Punjab & J&K, Operation Rhino and Operation Bajrang in the North East. Departmental units came to the aid of the civil authorities during industrial unrest and natural calamities, most famous being earthquake in Latur (Maharashtra), Uttarkashi in Garhwal Himalaya and the super cyclone in Odisha. The Ecological units have arrested man-made environmental degradation by planting 2.5 crore trees over 20,000 hectare of land in Mussoorie hills and Pithoragarh (Uttarakhand), Bikaner and Jaisalmer (Rajasthan) and ravines of Chambal in Madhya Pradesh.