The Stellar network has a built-in, fixed inflation mechanism. New lumens are added to the network at the rate of 1% each year. The network also collects a base fee for each operation in a transaction. The funds from base fees are added to the inflation pool.
As a balancing measure for the ecosystem, anyone who holds lumens can vote on where the funds in this pool go. Each week, the protocol distributes these lumens to any account that gets over .05% of the votes from other accounts on the network