- Yars’ Revenge is a video game released for the Atari 2600 in 1982. It was created by Howard Scott Warshaw, who also wrote the 2600 titles Raiders of the Lost Ark and the much-derided E.T. the Extra-Terrestrial. Yars’ Revenge was Atari’s best selling original title for the 2600.
- Chert (Wikipedia)
Chert (/ˈtʃɜːrt/) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood.