Shows the semantic difference between the terms "defaults", "options", and "settings". * A setting is what your program runs-with in this particular instance. * A default is what your program runs-with in the absence of a provided option. * An option is a user-provided value that overrides a default.

defaultsOptionsSettings.js

// assuming jQuery for its extend method.

// Calling program does this, and passes-in the options
var options = { validate: true, name: "bar" };

function myThing ( options ) {
  // Internally your program does this
  var empty = {}
  var defaults = { validate: false, limit: 5, name: "foo" };

  // The Keys to the City right here in this next line
  // Note: Defaults are preserved for subsequent calls
  // Note: User-provided options are preserved
  var settings = $.extend( empty, defaults, options) ; 

// ... etc using variable settings as required

}