• What is a Component?
  
  A practical definition is that a component is any piece of a software that you want to treat as a standard-issue "black box" chunk of functionality at design-time.

• What does a Component do?
  
  It has various aspects of functionality, including  compound documents, custom controls, inter-application scripting, data transfer, and other software interactions.  

• What language is a Component written?
     

     Components are written in different languages by different software vendors,
      in  different parts of the  world, and at different times.