Javascript deprecated

Probably some dumb questions from a noob, but I am attempting to use javascript and jquery.

1) Loading as a library in my one of my controller files,

$this->load->helper(array('url', 'html',));
$this->load->library('session');

works.

$this->load->library('jquery');

and other permutations like /javascript/jquery/  etc etc return Error Unable to Load but when I use the autoload.php function, as

$autoload['libraries'] = array('Javascript');

it works. Have I just not hit the right syntax or am I actually loading something I dont know about, or is my logging not telling me the right info?? (Actually, the logging says 'Javascript Class Initialized and loaded. Driver used: jquery.)

2) The CI User_Guide says javascript class is deprecated. Does this mean I am not supposed to use any java at all? Or is it the documentation is faulty and? I do not understand this.

Thanks for any help.