Once you have a jQuery object like the one you get by doing:
var car = $('li .car');
I saw code doing the following:
var carChildren = $(car).children('span');
What is the point of it?
Why not just use the .children method on the already jQuery var car like so?
var carChildren = car.children('span');
In short:
There is no reason for doing this. But it makes no difference in result too. It's basically just bad practice. So don't do it.
TL;DR
As said before, it makes no sense and it makes no difference. Let's think about what the lines do. To be clear we write it in one line:
var car = $('li .car');
var carChildren = $(car).children('span');
Is the same as:
var carChildren = $($('li .car')).children('span');
Nobody would ever do it this way! The reason someone would write $(car) is that they meight be confused by things like $(this), what often is write many times right after.
Why does it work anyway?
If you write $(car) jQuery will notice that car is already a jQuery object and replace it as it's context. But that is a unnecessary task what can be saved.
This said, you can directly use car as context too.
var carChildren = $('span', car);
function doSmthToCar(car) { $(car).children(...)}even if you are passing jquery objectvar car = $(); doSmthToCar(car). Otherwise it is just a wrong usage.