Funding in cryptocurrency refers to a mechanism used on futures trading platforms to maintain the price of perpetual contracts close to the spot price of the underlying asset.  

Traders with long (buy) or short (sell) positions periodically pay or receive a funding fee based on the difference between the perpetual contract price and the spot price.  

Purpose of funding:  
1. Balances demand between long and short positions.  
2. Prevents significant price divergence from the underlying asset.  

It’s a key metric for understanding market sentiment.