Finance service is the management, creation, and study of money and investments. Specifically, it deals with the questions of how an individual, company or government acquires money – called capital in the context of a business – and how they spend or invest that money. At the same time, and correspondingly, finance service is about the overall "system" i.e., the financial markets that allow the flow of money, via investments and other financial instruments, between and within these areas; this "flow" is facilitated by the financial services sector. Finance service therefore refers to the service of the securities markets, including derivatives, and the institutions that serve as intermediaries to those markets, thus enabling the flow of money through the economy. A major focus within finance service is thus investment management – called money management for individuals, and asset management for institutions.
As above, the financial service system consists of the flows of capital that take place between individuals (personal finance), governments (public finance), and businesses (corporate finance). "Finance" thus studies the process of channeling money from savers and investors to entities that need it.
In general, an entity whose income exceeds its expenditure can lend or invest the excess, intending to earn a fair return.