Bartik is the default theme for Drupal 7.
A huge thank you to the dozens of people who worked on this theme, and to everyone who supported the effort.
The Bartik theme comes with several regions.
regions[header] = Header regions[help] = Help regions[page_top] = Page top regions[page_bottom] = Page bottom regions[highlighted] = Highlighted regions[featured] = Featured regions[content] = Content regions[sidebar_first] = Sidebar first regions[sidebar_second] = Sidebar second regions[triptych_first] = Triptych first regions[triptych_middle] = Triptych middle regions[triptych_last] = Triptych last regions[footer_firstcolumn] = Footer first column regions[footer_secondcolumn] = Footer second column regions[footer_thirdcolumn] = Footer third column regions[footer_fourthcolumn] = Footer fourth column regions[footer] = Footer
These can be seen in action in the following screenshot:
The primary menu appears as tabs along the top of the page, below the header.
The secondary menu appears in the upper left corner.
The color module, if enabled, can be used to change the color of several parts of the Bartik theme, including the header (as a gradient), footer, link and text color.
The Bartik theme is named after Jean Bartik, one of the original programmers for the ENIAC computer.