Core competence: "A core competency is an area of specialized expertise that is the result of harmonizing complex streams of technology and work activity."
Core competencies are the majority important value generating skills within an organization and key areas of expertise which are different and only belonging to an organization. They are indispensive to the company's long term growth.
An organization’s core competencies are the things that they can do better than their competitors in the critical areas where the most value is added to the products. These areas of expertise can be any from sales and marketing to market research, from product development to human recourse management.