In the early days of domain registration, the dark times before the new generic top-level domains (gTLDs) were launched, it could be quite hard to find a domain that was both short and memorable.
Most of the good .COM domain names were taken, as were the more common words and phrases in various country code top-level domains (ccTLDs) like .CO.UK or .CA. So what do you do when there’s a shortage of something that’s in demand? Get creative. Especially on the internet where language is always evolving.