What's the difference between an entity tracking the total costs and an entity with the current price?

[bogdan.sv (Bohdan)]

Could you explain the difference between ‘Use an entity tracking the total costs’ and ‘Use an entity with current price’ when setting up the Energy panel?

[WallyR (Wally)]

I think it depends on what sensors you have available.
Some providers publish the current price and you can use that to calculate costs by having devices with meters included.
Some providers publish a total usage value directly.