Each IC has a 0.1 uF ceramic bypass capacitor across the Vcc and GND pins. A single 100 uF capacitor provides additional power supply filtering. It requires a +5 volt supply. A switch controls power and a green LED (D2) indicates power on.
The majority of chips are 7400 series LS family TTL devices. There are a few spare gates. Their inputs are grounded as per standard TTL design practice.