What's the difference between this.function and prototype.function?

[CuffeX]

Given simple JS inheritance, what's the practical difference in the base function between these two examples? In other words, when should a person choose to define a function on "this" instead of on the prototype (or the other way around)?For me the second example is easier to digest, but how much more is there to this?function defined on this:\[code\]//basevar _base = function () { this.baseFunction = function () { console.log("Hello from base function"); }};//inherit from basefunction _ctor() { this.property1 = "my property value";};_ctor.prototype = new _base();_ctor.prototype.constructor = _ctor;//get an instancevar instance = new _ctor();console.log(instance.baseFunction);\[/code\]function defined on prototype:\[code\]//basevar _base = function () {};_base.prototype.baseFunction = function () { console.log("Hello from base function");}//inherit from basefunction _ctor() { this.property1 = "my property value";};_ctor.prototype = new _base();_ctor.prototype.constructor = _ctor;//get an instancevar instance = new _ctor();console.log(instance.baseFunction);\[/code\]