Knowledge Base

Random grouping is just the start. This guide introduces three often-overlooked tools — counter, stopwatch/countdown, and scoreboard — so you can run your entire activity without pen and paper.

MD5 is a widely used hash function that converts data of any length into a fixed 128-bit digest. This guide explains how MD5 works, its known security vulnerabilities, and which scenarios still make sense for MD5 versus when you should use a stronger algorithm.

Shuffling a list seems trivial—just use a random number, right? Most intuitive approaches introduce subtle statistical bias. This article explains the Fisher-Yates shuffle algorithm, why it guarantees a perfectly uniform distribution, and how to implement it correctly.

Time zones are the invisible barrier in global collaboration. This guide explains UTC vs. GMT, how Daylight Saving Time works, the IANA time zone database, and practical tips for scheduling meetings and avoiding deadline mix-ups across time zones.

Jiaobei divination (掷筊) is a traditional Taiwanese temple practice where two crescent-shaped moon blocks are cast to interpret divine guidance. Learn what sheng jiao, xiao jiao, and yin jiao mean and how to perform it correctly.

Full-width characters occupy twice the space of half-width ones. Learn the definitions, key differences, conversion cases, and practical tips for handling full-width and half-width text in programming, data processing, and typesetting.

A Unix timestamp is the number of seconds elapsed since January 1, 1970, 00:00:00 UTC. Learn why it exists, how it works, how to convert it, and what the Y2038 problem means for your systems.

Manual grouping takes time and often feels unfair to students. The List Grouping tool lets you paste a roster, choose the number of teams, and get randomly shuffled groups instantly. This guide covers all the features, common use cases, and three tips for a smoother grouping experience.

The same draft can show one number in Microsoft Word and another in a website counter. Usually, neither side is wrong. They are just counting different things: words, characters, spaces, punctuation, formatting, and hidden content.