Flash swaps allow you to withdraw up to the full reserves of any ERC20 token on WhaleSwap and execute arbitrary logic at no upfront cost, provided that by the end of the transaction you either:
pay for the withdrawn ERC20 tokens with the corresponding pair tokens
return the withdrawn ERC20 tokens along with a small fee
Flash swaps aren't flash loans but can be used in the same way. They are incredibly useful because they remove upfront capital requirements and unnecessary constraints for multi-step transactions involving WhaleSwap.
For more information on using flash swaps, check out our tutorial: