Returns the index at whichvaluecan be found in thearray, or-1if value is not present in thearray. If you're working with a large array, and you know that the array is already sorted, passtrueforisSortedto use a faster binary search ... or, pass a number as the third argument in ...
Now multiple libraries are providing their own version of the$()function, so many now provide the option to turn off that definition in order to avoid clashes. Of course, you don't need to use a library to be able to use$(). All you need to substitute$()fordocument.getElementById()...