Function

• Source code functions as a blueprint to build the web page. When a programmer designs the source code for a web site, he defines the parameters of the web page in computer language. The finished web page differs from the source code just as a finished house looks very different than the pages of blueprints used to build it.
  
  

Original Code

• The programmer can write source code from scratch, entering the commands necessary for the finished page. She will choose one computer language from a wide variety of languages in use. Just as rules govern the proper use of spoken or written human language, rules guide the programmer as she writes.
  
  

Copied Code

• Another programmer may construct a web page using modules of code others have written to accomplish a particular task. For example, he can copy a module to calculate sales tax on an online purchase rather than taking time to write his own. So long as the module is written in the language he has selected for the page, it will work on his page as it does on others. Many vendors offer source code modules for particular tasks.
  
  

Considerations

• Programming language conforms to the needs of the computer rather than human eyes. The instructions may appear buried in gibberish. All of the spacing, symbols and characters used in the source code carry meaning for the computer processing the information. Any change to the source code changes the way the computer builds the web page.
  
  

Warning

• Many sites offer source code for download. Some reputable companies provide code, while others are scams. Use caution when selecting a site for code. Unscrupulous individuals may include viruses or other harmful programming hidden within the code being offered.
  
  

Fun Fact

• Build-your-own-web-page sites such as blogs allow users to enter pertinent information into templates, and then use the data to build source code to create the page.