Network Fee (Transaction Fee)
Quick definition
The fee paid to miners for confirming your Bitcoin transaction — separate from exchange fees.
Every on-chain Bitcoin transaction pays a fee that goes to miners. It's set by supply and demand for block space: busy network, higher fees; quiet network, lower.
It's separate from whatever your exchange charges. Wallets estimate it for you and let you choose faster (pricier) or slower (cheaper). The Lightning Network makes small payments nearly free.