A telescope's main function is to gather light. If you don't gather enough light, you won't see anything, no matter how much magnification you throw at it. The aperture, or opening through which skylight passes, is what matters. The brighter the object, the smaller the value. The faintest star that can be seen by the naked eye is about magnitude 6.
Every telescope has either a primary lens or mirror that is used for collecting light.
Putting it in practical terms, an 8-inch, given a dark, clear sky and good seeing conditions, should be able to detect stars as faint as magnitude 14 or better. This is more than 380,000 times fainter than the faintest star seen by the naked eye, which is usually considered to be magnitude 6. Even a small telescope allows the eye to see millions of stars that the naked eye cannot. More light gathering area translates into a more detailed image, that is more information. Now, bear with me while we let out a little more air from this term.