According to
Wikipedia,
Numismatics is the study or collection of currency, including coins,
tokens, paper money, and related objects. While numismatists are
often characterized as students or collectors of coins, the
discipline also includes the broader study of money and other
payment media used to resolve debts and the exchange of goods.
Many items have been used as money, from naturally scarce precious
metals and cowry shells through cigarettes to entirely artificial
money, called fiat money, such as banknotes. Modern money (and most
ancient money too) is essentially a token – an abstraction. Paper
currency is perhaps the most common type of physical money today.
However, goods such as gold or silver retain many of the essential
properties of money.
Exonumia is the study of coin-like objects such as token coins and
medals, and other items used in place of legal currency or for
commemoration. This includes elongated coins, encased coins,
souvenir medallions, tags, badges, counterstamped coins, wooden
nickels, credit cards, and other similar items. It is related to
numismatics proper (concerned with coins which have been legal
tender), and many coin collectors are also exonumists.
Notaphily is the study of paper money or banknotes. It is believed
that people have been collecting paper money for as long as it has
been in use. However, people only started collecting paper money
systematically in Germany in the 1920s, particularly the
Serienscheine (Series notes) Notgeld. The turning point occurred in
the 1970s, when notaphily was established as a separate area by
collectors. At the same time, some developed countries such as the
USA, Germany and France began publishing their respective national
catalogues of paper money, which represented major points of
reference literature.
Scripophily is the study and collection of stocks and Bonds. It is
an interesting area of collecting due to both the inherent beauty of
some historical documents as well as the interesting historical
context of each document. Some stock certificates are excellent
examples of engraving. Occasionally, an old stock document will be
found that still has value as a stock in a successor company.
Given below are some of the useful
links to deeper knowledge about the coinage of India:
http://en.wikipedia.org/wiki/Numismatics
http://www.rbi.org.in/scripts/restrospectcoins.aspx
http://www.rbi.org.in/scripts/mc_mughal.aspx
http://www.rbi.org.in/scripts/mc_british_WilliamIV.aspx
http://www.rbi.org.in/scripts/mc_british_QueenVictoria.aspx
http://www.rbi.org.in/scripts/mc_british_EdwardVII.aspx
http://www.rbi.org.in/scripts/mc_british_GeorageV.aspx
http://www.rbi.org.in/scripts/mc_british_GeorageVI.aspx