Inscriptions are permanent writings engraved on hard surface such as stone, metal or terracotta. Study of inscriptions is called epigraphy. The earliest inscriptions were written on stone. They usually record the achievements, activities and ideas of those who got them inscribed.
So, we get inscriptions which glorify the exploits of kings or mention donations made by men and women for religious purposes.
Those inscriptions which are composed by poets in praise of kings and patrons are known as prashastis. Some inscriptions carry dates. Others are dated on the basis of palaeography or style of writing, with a fair amount of precision. The earliest inscriptions were in Prakrit, a name for language used by ordinary people. In later times, Tamil and Sanskrit were also used to write inscriptions.
The Mauryan king Ashoka was the first person to issue inscriptions. Most of his inscriptions are in Prakrit language written in the Brahmi script though, some in the northwest, were written in Kharosthi. The Aramaic and Greek scripts were used for inscriptions in Afghanistan so that the local people could understand their subject matter
The Brahmi script was first deciphered in 1837 by James Princep who was civil servant during the British rule. Brahmi was written from left to right like Hindi while Kharosthi from right to left. Ashokan inscriptions help greatly in understanding his religious and administrative policies.
From the first century B.C. the kings started granting land to religious people. The Satavahans kings of the Deccan were the first ones to do so. These inscriptions record the concessions granted to the donee (the receiver of grant). Such inscriptions help in finding out the religious and economic activities of the period. Some of these inscriptions are written on stone but most on copper plates. The copper plate charters were probably given as a record of the transaction to those who received the land and were granted concessions.
However, there are some limitations of inscriptional evidence. For example sometimes, letters are very faintly engraved, and thus reconstructions are uncertain. Also, inscriptions may be damaged or letters missing. Besides, it is not always easy to be sure about the exact meaning of the words used in inscriptions, some of which may be specific to a particular place or time.