Computers are naturally logical entities, producing results that are a function of exactly what is input into them. In the real world, things aren’t always so logical, and you may need your computer to exhibit random output for applications involving simulation, security, and even gaming.
To help your computer act a bit more erratic, GRAND is a TRNG, that is a True Random Number Generator, which plugs in to your computer as a USB stick. While the computer itself can exhibit some randomness, according to GRAND’s product listing, “Depending on the workload, the entropy collected automatically by the [computer’s] kernel might not be sufficient to generate the random numbers at the requested rate.”
To solve potential entropy deficiencies, GRAND pumps in randomness at a rate of up to 800 KBytes/s (or more than 6 Mbps) using an onboard STM32 chip. It even does a chi-squared check to ensure the quality of the data’s randomness. Data is passed to the main computer via a virtual serial port, and it features both a green LED to show when it’s sending, and a red LED to indicate that the data flow is stopped if it failed the randomness test.
For another randomness option, you might also check out Infinite Noise USB TRNG. It plugs in like the GRAND, but uses different techniques to generate values.