The speed at which 6 gigabytes of data is consumed depends on what activities are performed. For example, streaming one hour of music uses about 20 megabytes of data, but streaming an hour of high-definition video uses about 810 megabytes of data. For perspective, one gigabyte is 1,024 megabytes.
The type of device is also an important factor; for instance, a desktop computer uses more data than a smart phone. This is because the high-definition resolution of a desktop is higher than that of a typical smart phone, though there are exceptions to this rule. Some cell phone providers offer data calculators that are helpful with estimating out how much data various activities use.