Javascript syntax confusion

Question

Saw this in here JavaScript : For loop with timeout. Can someone explain to me what is the (i)? I dont see syntactic pattern such as this very often.

for (var i=0;i<=10;i++) {
   (function(ind) {
       setTimeout(function(){console.log(ind);}, 3000);
   })(i);
}

If someone can also share the documentation with great details explaining (i), that would be great! Thank you