var color='red';
var o={color:'blue'};
function sayColor(){
console.log(this.color);
}
sayColor();//"red"
sayColor.apply(o);//"blue" 

var color='red';
var o={color:'blue'};
function sayColor(){
console.log(this.color);
}
o.sayColor=sayColor;
o.sayColor();//"blue" 

var color='red';
var o={color:'blue'};
function sayColor(){
console.log(this.color);
}
sayColor();//"red"
sayColor.apply(o);//"blue" 

average(,,);
average();
average(,,,,,,,,);
average(,,,,,,,,,); 

averageOfArray([,,]);
averageOfArray([]);
averageOfArray([,,,,,,,,]);
averageOfArray([,,,,,,,,,]); 

var scores=getAllScores(); 

var scores=getAllScores();
average.apply(null,scores); 

var scores=getAllScores();
averageOfArray(scores); 

var buffer={
state:[],
append:function(){
for(var i=,n=arguments.length;i<n;i++){
this.state.push(arguments[i]);
}
}
}; 

buffer.append('Hello,');
buffer.append('firtName',' ','lastName','!');
buffer.append('newLine'); 

buffer.append(arg1,arg2,arg3,...) 

buffer.append.apply(buffer,getInputStrings()); 

function average(){
var args=[].slice.call(arguments);
var sum=args.reduce(function(prev,cur){
return prev+cur;
});
return parseInt(sum/args.length,);
} 

function averageOfArray(arr){ 
var sum=arr.reduce(function(prev,cur){
return prev+cur;
});
return parseInt(sum/arr.length,);
} 

var color='red';
var o={color:'blue'};
function sayColor(){
console.log(this.color);
}
var oSayColor=sayColor.bind(o);
oSayColor();//"blue" 

if (!Function.prototype.bind) {
Function.prototype.bind = function(oThis) {
if (typeof this !== 'function') {
// closest thing possible to the ECMAScript 
// internal IsCallable function
throw new TypeError('Function.prototype.bind - what is trying to be bound is not callable');
}
var aArgs = [].slice.call(arguments, ),
fToBind = this,
fNOP = function() {},
fBound = function() {
return fToBind.apply(this instanceof fNOP? this: oThis,
aArgs.concat(Array.prototype.slice.call(arguments)));
};
if (this.prototype) {
// Function.prototype doesn't have a prototype property
fNOP.prototype = this.prototype; 
}
fBound.prototype = new fNOP();
return fBound;
};
}