Fiber-optic Internet is the fastest Internet. Internet and TV) are offered by many major fiber providers, as are triple-play packages (Internet + phone + TV). Because fiber cables are made of glass and signals travel through them without electricity, they are immune to external disruptors such as temperature, inclement weather, and humidity. The other way to get this technology is if the ISP in your area decides to upgrade its network from cable to fiber.
If it's important to you to get the fastest internet possible, you may decide that the high upfront costs that are often associated with installing fiber optics are worth it. That said, homes and offices with many Internet users will appreciate the fast and reliable connection of optical fiber. If it's important to you to get maximum reliability from the Internet, arguably you can't do anything better than fiber-optic service. FTTN is where fiber cable is terminated in a hub near your home, and the final distance to your house is done with traditional cable.
Fiber-optic Internet is available in select areas and for certain households; if you live in an area covered by a provider that places fiber cables to homes that aren't already routed for it, you're in luck; Xfinity is one of those providers. All the speed and reliability offered by fiber comes at a cost, as it tends to be one of the most expensive ways to connect to the web. Because fiber is a relatively new technology and installation is quite complicated (unlike DSL or cable that leverage existing infrastructure), it is only available in select areas of the country. While fiber-optic internet is a big improvement, regular users may not notice the difference with high-speed cable, which in some cases is capable of offering a speed close to that of fiber.