From one theme, many.

Every WordPress theme is different, built by different developers offering different advantages and disadvantages and each with their own learning curve for you the developer to become proficient with.

In this discussion learn how selecting a theme on it’s functionality and not on it’s outward appearance can be one of the most significant decisions you make in your development workflow. By learning how to customize a theme to make it’s outward appearance anything you need it to be, the selection of the theme based on functionality becomes far more important.

Once you learn the underlying functions of a solid theme, you can then leverage that knowledge to more quickly and easily build any website you need creating several websites on the solid foundation of a strong underlying WordPress theme.