Sam Altman's Worldcoin crypto is running out of 'orbs.' But what are orbs?

Worldcoin, a cryptocurrency project founded by OpenAI CEO Sam Altman that has seen rapid growth, is now running low onorbs — the devices used for iris scans in exchange for tokens. Worldcoin has decided to increase Orb production to meet high demand and logistical challenges. source: https://qz.com/worldcoin-cryptocurrency-orbs-shortage-sam-altman-1851438149