Circulating Supply refers to the number of coins or tokens of a specific cryptocurrency that are publicly available to buy or sell. If you can trade them, they are considered circulating.
The more coins are added to circulation, the more the value decreases. Conversely, the more coins are burned or removed from circulation, the more the value increases.
Luna Price Crash
Before the dramatic price collapse, Luna's circulating supply was in the range of 340 million to 350 million. However, on May 10, this jumped to 386 million, before hitting 1.5 billion on May 11. By May 12, this circulating supply was at over 176 billion. This led to a huge loss of users’ money who had bought luna before the price crashed.