What is the meaning of the expression ${variable_name} in jQuery?

I know the dollar sign $ refers to the jQuery object but 开发者_C百科I don't know that the curly braces {} that follow do.

Is ${variable_name} referring to a jQuery attribute?

Thanks.

${} Template Tag :- Used for insertion of data values in the rendered template. Evaluates the specified field (property) on the current data item, or the specified JavaScript function or expression.

more details here

http://api.jquery.com/template-tag-equal/