The Unit Heading The unit heading specifies the unit's name. It consists of the reserved word unit, followed by a valid identifier, followed
by a semicolon. For applications developed using Borland tools, the identifier must match the unit file name. Thus,
the unit heading
unit MainForm;
would occur in a source file called MainForm.pas, and the file containing the compiled unit would be MainForm.dcu
or MainForm.dpu.
Unit names must be unique within a project. Even if their unit files are in different directories, two units with the same
name cannot be used in a single program.
