Why are transaction fees necessary when sending Bitcoin? - Infographic

Confirmation fees act as an incentive for miners, in addition to the standard block reward.

Spam attacks from anyone seeking to overload the network are reduced when transactions have a fee.

Fee cost is automatically determined by how much data is being transferred, not the dollar amount of the transaction.

Miners can choose to set their fee amount higher or lower than the standard amount defined by the protocol.

Fees on transactions with a data size less than 1000 bytes, and a spend value higher than 0.01 BTC are not required.

Not including a fee could increase wait times to days instead of minutes.