More specifically, what is a project? It's a temporary endeavor undertaken to create a unique product, service or result.
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.
Project management, then, is the application of knowledge, skills, tools, and techniques to project activities to meet the project requirements.