A commercial bank's primary liabilities are deposits and primary assets are loans and bonds. As per the U.S. Banking Act of 1971, the "commercial bank" is an institution that offers demand deposits and originates loans. Therefore, a money market mutual fund is not a commercial bank as it does not originate loans. Similarly a finance company is also not a commercial bank as it does not offer demandable deposits. The term "commercial" distinguishes a commercial bank from an investment bank.

Its primary liabilities are deposits and primary assets are loans and bonds. As per the U.S. Banking Act of 1971, the "commercial bank" is an institution that offers demand deposits and originates loans. Therefore, a money market mutual fund is not a commercial bank as it does not originate loans. Similarly a finance company is also not a commercial bank as it does not offer demandable deposits.

The term "commercial" distinguishes a commercial bank from an investment bank.

Commercial banking activities are different from those of investment banking, which include underwriting, acting as an intermediary between an issuer of securities and the investing public, facilitating advices on mergers and other corporate reorganizations like turnovers and acquisitions, and also acting as a broker for institutional clients.

Commercial banks are so named because they specialize in loans to commercial and industrial businesses. Commercial banks are owned by private investors like stockholders or by bank holding companies. The majority of commercial banks are owned by bank holding companies. The sole objective of commercial banks is to make a profit. Commercial banks are owned by private investors, called stockholders, or by companies called bank holding companies

Apart from other banking functions, since late 20s, most of the commercial banks in developing countries have been entering into micro-finance market also in which they will provide soft loans based on character rather than collaterals to small businesses, small farmers and micro-entrepreneurs. In this way Commercial banking has become an essential sector of the modern economy by fulfilling the financial needs of all segments of the economy.