The flexibility of WordPress is apparent when discussing terminology related to the design of a WordPress blog. At the core of WordPress, developers created a programming structure named The Loop to handle the processing of posts. The Loop is the critical PHP program code used to display posts. Anyone wanting to enhance and customize WordPress will need to understand the mechanics of The Loop.
Widgets provide an easy way to add little programs, such as the current weather, to a sidebar.
Menus make it easy to define the navigation buttons that are typically present near the top of a site’s pages.
The Background tool allows the user to change the background image and color of a site.
The Header tool gives the user control of the images displayed at the top of a site’s various pages.
Formats allow the user to control the display of a specific post (i.e. display this post as an Aside or as a quote or as a gallery). The WordPress Twenty Twelve theme is an excellent example of a theme that uses these tools.
And speaking of the WordPress Twenty Twelve theme, developers and users are encouraged to explore that theme in detail. The WordPress Twenty Twelve theme, developed by the WordPress community, demonstrates the use of tools such as Menus and Widgets, provides examples of recommended theme coding techniques, and emphasizes the use of the Child Theme concept to shield a theme from getting overwritten during a WordPress update.