Here is an example of how to create custom objects and properties using the Constructor Function.

Usually you can get by with using JavaScript's built-in objects, built-in properties and built-in methods. But imagine the power in creating your own!

A few things to remember about constructor functions:

1. Constructor Function names usually begin with a capital letter (but not always!).
   
   
2. Variables defined within the function body use the "this" keyword. These variables become properties of any new object that is based on the function.
   function Table(){
   this.tableOpen = "<table>"
   this.trOpen = "<tr>"
   this.text = "This table was created with JavaScript"
   this.tdClose = "</td>"
   this.trClose = "</tr>"
   this.tableClose = "</table>"
   }
   
   
   
3. Constructor functions can be extended in two places: to another function or to a new object. In both cases, the extended objects inherit the properties of the function it extended.
• When extending to another function so that the new function has access to another function's properties, use this syntax:
  function GreenTd() {
  this.tdOpen = "<td bgcolor=\"green\">"
  }
  GreenTd.prototype = new Table()
  
  
• When extending to a new object, use this syntax:
  GreenTable = new GreenTd()



4. To reference the properties, append the object name with a period followed by the property name:
   GreenTable.tableOpen
   GreenTable.trOpen

Then write it to the page:
document.write(GreenTable.tableOpen)
document.write(GreenTable.trOpen)

Now lets add an argument

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