Wikipedia: What is a Public Utility?
A public utility company (usually just utility) is an organization that maintains the infrastructure for a public service (often also providing a service using that infrastructure). Public utilities are subject to forms of public control and regulation ranging from local community-based groups to statewide government monopolies.
Public utilities are meant to supply goods and services that are considered essential; water, gas, electricity, telephone, waste disposal, and other communication systems represent much of the public utility market.
Wikipedia: What is Infrastructure?
"installations that form the basis for any operation or system"
A way to embody personal infrastructure is to think of it in terms of human capital.
Infrastructure is the set of facilities and systems that serve a country, city, or other area,[1] and encompasses the services and facilities necessary for its economy, households and firms to function.[2] Infrastructure is composed of public and private physical structures such as roads, railways, bridges, tunnels, water supply, sewers, electrical grids, and telecommunications (including Internet connectivity and broadband access). In general, infrastructure has been defined as "the physical components of interrelated systems providing commodities and services essential to enable, sustain, or enhance societal living conditions" and maintain the surrounding environment.
One way to describe different types of infrastructure is to classify them as two distinct kinds: hard infrastructure and soft infrastructure.[4] Hard infrastructure is the physical networks necessary for the functioning of a modern industrial society or industry.[5] This includes roads, bridges, and railways. Soft infrastructure is all the institutions that maintain the economic, health, social, environmental, and cultural standards of a country.[5] This includes educational programs, official statistics, parks and recreational facilities, law enforcement agencies, and emergency services.
Wikipedia: What is a Public Service?
A public service or service of general (economic) interest is any service intended to address specific needs pertaining to the aggregate members of a community.[1][2] Public services are available to people within a government jurisdiction as provided directly through public sector agencies or via public financing to private businesses or voluntary organizations (or even as provided by family households, though terminology may differ depending on context). Other public services are undertaken on behalf of a government's residents or in the interest of its citizens. The term is associated with a social consensus (usually expressed through democratic elections) that certain services should be available to all, regardless of income, physical ability or mental acuity. Examples of such services include the fire brigade, police, air force, and paramedics (see also public service broadcasting).
Even where public services are neither publicly provided nor publicly financed, they are usually subject to regulation going beyond that applying to most economic sectors for social and political reasons. Public policy,[3] when made in the public's interest and with its motivations, is a type of public service.