$
is the jQuery object itself, which when called implements a whole pile of different interfaces. $('string')
runs a selector or constructs a node; $(domElement)
wraps an element… and $(a_function)
is a convenient short hand for $(document).ready(a_function)
. See the jQuery API docs for (much) more information.
A note in passing: $(function () { ... })
is shorter, but if you ever want to search for all of your on-ready events, you might be wishing that you had .ready
to search for 🙂