Charge
A Charge is a resource that is generate onto tiles on your board. It can be generated by charge-generating tiles, such as Tallow Candle, or by card effects, such as Pyrite Flakes.
Some machines require charge input to operate (indicated by a green-input IO-band) and others can operate normally but have an special effect when powered (indicated by a green dot below their name).
Charges are often generated during the Setup Phase of each Round, and can be moved through pipes and IO Bands during the Propagate Step; they are always cleared up at the end of each Round.