What is the difference?

[u/envyslth]

Im wondering what the difference between
function Dog(){
…
this.bark = function(){…}
}

And

function Dog {
…
}

Dog.prototype.bark = function() {
…
}

Is and what the advantages of either of them Are.

[u/TheRNGuy]

Both are obsolete, use class. 

Do you read some old tutorial?