What is project?

As per PMBOK Guide the definition of a Project is "A Project is a temporary endeavor undertaken to create a unique product, service or result." That means it have two criteria  a) it will have definite start and end, b) it will have a unique deliverable or output which could be either tangible or intangible. For example, developing a new plane with new aerodynamic shape is a project but once its created the project is completed. The project will not continue during the plane will be in use and till the plane completes its product lifecycle nor the project will continue while company starts generating same type of plane in commercial development line. Cause regularly developing planes in commercial development line is an iterative job and thats called operation not project.

Again as per PMBOK Guide, a project can create either of following three:

a)  A Product that can be either a component of another item or an end item in itself
b)  A Capability to perform a service (e.g., a business function that supports production or distribution). or
c)  A result such as an outcome or document (e.g., a research project that develops knowledge that can be used to determine whether a trend is present or a new process will be benefit society)