"A project is temporary in that it has a defined beginning and end in time, and therefore defined scope and resources.
And a project is unique in that it is not a routine operation, but a specific set of operations designed to accomplish a singular goal. So a project team often includes people who don’t usually work together – sometimes from different organizations and across multiple geographies.

The development of software for an improved business process, the construction of a building or bridge, the relief effort after a natural disaster, the expansion of sales into a new geographic market — all are projects.
And all must be expertly managed to deliver the on-time, on-budget results, learning and integration that organizations need.

Project management, then, is the application of knowledge, skills, tools, and techniques to project activities to meet the project requirements.
It has always been practiced informally, but began to emerge as a distinct profession in the mid-20th century. PMI’s A Guide to the Project Management Body of Knowledge (PMBOK® Guide) identifies its recurring elements:

Project management processes fall into five groups:
Initiating
Planning
Executing
Monitoring and Controlling
Closing
"