- The Apple II (stylized as apple ][) is a personal computer released by Apple Inc. in June 1977. It was one of the first successful mass-produced microcomputer products and is widely regarded as one of the most important personal computers of all time due to its role in popularizing home computing and influencing later software development.
- Absolute magnitude (Wikipedia)
In astronomy, absolute magnitude (M) is a measure of the luminosity of a celestial object on an inverse logarithmic astronomical magnitude scale. An object’s absolute magnitude is defined to be equal to the apparent magnitude that the object would have if it were viewed from a distance of exactly 10 parsecs (32.6 light-years), without extinction (or dimming) of its light due to absorption by interstellar matter and cosmic dust. By hypothetically placing all objects at a standard reference distance from the observer, their luminosities can be directly compared among each other on a magnitude scale. For Solar System bodies that shine in reflected light, a different definition of absolute magnitude (H) is used, based on a standard reference distance of one astronomical unit.