For example, what does no impermanent lost mean?
As for the description of impermanent loss then it means the opposite of it. Or you mean to say the exact as impermanent loss?
What is impermanent loss?
Impermanent loss happens when you provide liquidity to a liquidity pool, and the price of your deposited assets changes compared to when you deposited them. The bigger this change is, the more you are exposed to impermanent loss. In this case, the loss means less dollar value at the time of withdrawal than at the time of deposit.
As far as I know coins have
1. stacking
2. liquidity provider
3. p2p lending
which one is which?
Number 1 is staking, it's different from stacking.
The impermanent loss is usually happening on number 2 which is being a liquidity provider.