Prior to the introduction of CSS, web pages were rather plain and layouts were nearly non-existent. In 1996, the invention of CSS helped offer new opportunities. Some web designers used tables which enabled a visual layout, however, they offered little flexibility and were not efficient. Over the years other methods such as floating/clearing methods evolved and sometimes included inline and block methods to help control how a layout would be rendered in an html page. Sometimes other methods like positioning offered more control but limited how easily the web site could be adapted. These methods helped build more visual web design layouts, however, they were never intended for layout purposes. The challenges with these approaches have become more apparent as responsive web designs are in more demand.
Flexbox definitely has a lot more to it than this one line of css, however, for now – this is the core concept we need you to master this week before we learn more properties that you can apply. This requires you to not only learn what this display: flex; code does but you will need to master nesting html elements and understand what a parent, or container, is and what a child, or item is. Please note your class names certainly could be different, however, it is wise to name so that you will easily remember each section of your site.