Writing some code
Already it is time for us to write something. This first example will have no use at all except to demonstrate some basic concepts of component writing.

First of all, select Component from the main Delphi menu and then select New Component. Enter TComponent as the "Ancestor type" and TFirstComponent as the name of your component. Next click the "Install" button.

At this point you may either install your new component into an existing package (a package holds a collection of components) or install into a new package. Click "into new package" and click the "Browse" button.

Once you have selected a path and filename for your new package and entered a description click "OK". At the next dialog (asking if you would like to recompile your package) click "Yes". Once the package is compiled and installed, save your package and unit.

At this point we have specified our base class, and also our new class name. We have created a new package to contain our component and have been presented with a skeleton class structure by Delphi.

If you look at the source code provided by Delphi you will now see the Private, Protected, Public, and Published sections.

   Encapsulation
Encapsulation is a simple concept to grasp, but extremely important to component writing. Encapsulation is implemented with the use of four reserved words: Private, Protected, Public, and Published, you will see the Delphi has included these sections automatically in the source code for your new component.

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