74HC00, 74HC191, 74HC4511
Let's make a decimal counter using a counter IC. You can see by the schematic that the counter IC output is decoded with a decoder IC and display the result in decimal numbers on the LED display.
When you finish assembling, turn power ON.
At this time, all LEDs are OFF and 0 is shown on the LED display.
Press S1 to send the pulses to the counter IC.
The display changes to 1, 2, 3..and so on. At the same time, you'll notice the four LEDs blinking ON and OFF as shown in Figure 1.
Keep pressing S1, and the number reaches 9 and return to 0, then change again to 1, 2, 3, ... and so forth. This counting operation repeats over and over again so long as you keep pressing S1.