Differentiate between pure-click companies and brick-and-click companies

What will be an ideal response?

Pure-click companies are those that have launched a Web site without any previous existence as a firm, while brick-and-click companies are existing companies that have added an online site for information or e-commerce.
There are several kinds of pure-click companies: search engines, Internet service providers (ISPs), commerce sites, transaction sites, content sites, and enabler sites. Brick-and-click companies are formed by adding an e-commerce channel to an existing business.