I have this code and i don't understant why my var i is equal to linksLen when i try to use it, can you explain to me please why?:
var links = document.getElementsByTagName('a'),
linksLen = links.length;
for (var i = 0 ; i < linksLen ; i++) {
links[i].addEventListener('keydown',function(e){
if(document.getElementById('overlay').style.display =='block'){
if (e.keyCode === 39) {
alert(i);
}
}
});
}
};