A map that gives a complete picture of the natural as well as cultural elements in a small geographical area is called a "topographic map".
It gives a complete description of the place.
Arrangements for the preparation of topographic maps of the Indian Territory were made in $1905.$
At that time India and its present neighbors were under British rule.
So all these regions were included in this scheme.
Y k covers an area equal to $1^\circ$ degree.
Hence it is also called degree sheet.
Previously this map measured $1$ inch: $4$ miles.
It is also called a quarter inch map as it shows a distance of $1$ mile in $¼$ inches.
The scale on this map is $1: 50,000.$
They are also called one-inch maps because previously the measurement of such diameters was $1$ inch: $1$ mile.