I worked at a Thai company for 2 months and kept seeing Thai people type 555 in chat. I thought it was some kind of code or number but did not understand. One day the boss sent a report for me to review and there was a number error. I replied saying the numbers in the report are wrong 555 meaning page 555. The boss was quiet for a while then replied sorry where is this funny. That is when I learned 555 means laughing because 5 in Thai is ha so 555 sounds like hahaha. I was so embarrassed!