what does $.functionName(); mean in javascript?

Question

I am not familiar with this syntax. What does the $. mean before the function call?

Answer 1

$ is just a name of some object. It could be jQuery, or Prototype, in case you're using one of these libraries.

So $.functionName() simply stands for calling a function named functionName of the object named $.

Answer 2

Over here $ sign can be replaced with "jQuery " keyword.

$.functionName();

is the same as

jQuery.functionName();

if you are using jQuery framework. If using something else, it may refer to base object as in jQuery.