These are image-based tabs.

These tabs use additional settings, so selected tab looks like it was brought to the front.
This effect is achieved with the help of additional items (separators) which have individual styles. So, the tabs have the following structure:

Item1 separator Item2 separator Item3 separator Item4

Where separator is the additional item, that creates bring-to-front effect.
Each separator has 7 states:

                                   

For more details see parameters info.

These are Glass Style tabs.

You should paste your content here...

These are image-based tabs.