Each type of selector has a `#header.callout` is the element with both id=header and class=callout, while `#header .callout` is child with class=callout of the element with id=header. style. They are listed as follows: Core Functionality Provides the core features of the library as well as many helpful utility methods. p 0 0 1 1 But, I dont know if I blame the example or is something fishy here. tuesday,wednesday,Thursday here is a select picker Note: Seperate each class with a comma. They look nearly identical, but the top one has no space between #header and .callout while the bottom one does. All the selectors are grouped into categories. This is an unobstrusive jQuery plugin which is a drop-in replacement for the standard