Most public sector entities seek to provide services to individuals and companies and deal with laws and regulations. There is no profit motivation in the public sector. However, financial management is still important.
The public sector is a major component of economies around the world, and it is similar in many ways to the private sector. In fact, most public sector jobs have equivalent jobs in the private sector. The motivation for public sector work, however, is different than private sector work. Instead of working toward the goal of collecting a profit, public sector entities seek to provide services, regulate activities and enforce laws.
When many people think about public sector work, they think about bureaucracies and offices. However, most teachers and police officers work in the public sector, and health care administrators often work in the public sector as well.
Certain jobs are best done by the government. Having multiple companies operating completely different roads that charge for access, for example, would be impractical, and the government has an interest in ensuring accessible transportation. In many cases, however, public sector work is outsourced to private sector companies. Instead of hiring workers to maintain roads, some government agencies choose to hire a company to take care of the roads.