Godown is the place where company stores goods and material generally.

For each company which is maintaining accounts with inventory, Tally creates a default godown named “Main Location”

In order to change the details of Main location (or) to maintain multiple godowns enable the following option:
F11(features)–>F2(Inventory features)–>
Maintain multiple godowns:yes

Once godowns option is enabled, we can create or manage godowns using:
GOT–>Inventory Info–>Godowns

we can create primary or sub godowns.
Godown created under primary will be called primary or main godown.
Godown created under a main godown is known as sub godown.

To provide additional details (like address etc) for the godown:
being in Godown creation/alteration–>Press F12