- capacitor just stores. there is no current flow between terminals.
- time to charge a capacitor is determined by the rc time constant:
t = r*c.
looked at rc integrator circuits:

and rc differentiator circuits.
briefly spoke about semiconductors.
spoke about diodes having forward or reverse biasing.
looked at and & or gates made with diodes.

an example would be a power block diode circuit.

only when anode > cathode, current flows.
when led is forward biased, photons get fired.
flat side in led is cathode.
spoke about multiplexing and charlieplexing.

arrow always points towards the n gate in a transistor.