Artifacts are the physical or tangible by-product of a project's process or deliverables.
Artifacts are the by-products of a project's processes or production of deliverables. They often contain information that is produced through the life-cycle of the project. This could range from project documentation (project plans, lessons learned, meeting minutes, etc.) to functional documentation (requirements gathering, user guides, release notes, etc.). While the type of document or output may be different across projects, the common factor is that the artifact will be created specifically to meet needs within the current project.
In some projects, artifacts may also be referred to as the project deliverables.