Before, and for several years after, Microsoft started bundling IE, many, perhaps most, ISPs (dialup and what passed for "broadband" at the time) typically delivered software CDs that you were expected to install with their own software (often including their preferred web browser, preconfigured with their preferred start page and other settings.)

If you just bought your first computer at that time, you weren't likely to have internet service to connect it to until you bought that separately, and when you did, you would have software, too.