infrastructure

Infrastructure is generally a set of interconnected structural elements that provide the framework supporting an entire structure. The term has diverse meanings in different fields, but is perhaps most widely understood to refer to roads, airports, and utilities. These various elements may collectively be termed civil infrastructure, municipal infrastructure, or simply public works, although they may be developed and operated as private-sector or government enterprises. In other applications, infrastructure may refer to information technology, informal and formal channels of communication, software development tools, political and social networks, or shared beliefs held by members of particular groups. Still underlying these more general uses is the concept that infrastructure provides organizing structure and support for the system or organization it serves, whether it is a city, a nation, or a corporation.

Disposable/Discretionary income

Another concept that is often confused with disposable income is discretionary income. This is equal to disposable income minus the cost of the fixed expenses of life (such as rent/mortgage, food, car payments, insurance, etc.). It is income that can be saved or spent on goods and services wanted, not needed. Disposable income is gross pay minus taxes and deductions. In other words, disposable income is the same as "net pay". Unfortunately, the definition of discretionary income is fuzzier than that of disposable income, making it harder to measure.
When applying for a loan or a mortgage, banks often refer to the customer's "disposable income" — based on the information here, the term they should be using is actually "discretionary income