What does impermanent loss mean?

Impermanent loss is the price difference between holding an asset on a centralized exchange or wallet and adding it as liquidity on Uniswap or other decentralized exchanges. Most decentralized exchanges are programmed using the constant product market maker function x*y equals k which means that the amount of one currency added must be the same as the other when providing liquidity. Swapping cryptocurrency on these exchanges like Unisawp means that you are taking from either x and or y and they must add up to k which determines the new price of both assets on the exchange. Liquidity providers or market makers who put their funds on these exchanges to make trade possible and earn rewards run the risk of having the value of their asset less than the actual market value of the market when the value of their tokens go down as a result of volatility caused by swaps which are market activities. If the LP provides remove their funds at this point the loss becomes permanent. Otherwise, arbitrageurs can buy from the pools and sell on other exchanges to maintain a stable price.