The single.php file displays single (individual) posts.
Following is a description of the contents of the single.php file in the theme:
In Starkers, the single.php file displays a link to the previous post, then the title of the current post, followed by the content of the post. The comments template is called to display a comments area for the post in which the viewer of the post may leave comments about the post.
The Starkers theme still contains many other php files. Still to come are archive.php, attachment.php, author.php, category.php, comments.php, functions.php, onecolumn-page.php, search.php, sidebar-footer.php and tag.php. I will start with the functions.php in the Starkers theme, a key element to any theme is the functions php file.