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Now that a pin is listening, you can ask it what it sees. The function digitalRead checks a pin and tells you its current state.

digitalRead gives back just two answers: HIGH or LOW. That is perfect for a button, which is only ever pressed or not.

Save the result in a variable so you can use it. Here state holds whatever digitalRead found on pin 2 at that moment.

Reading only works if you prepared the pin. Call pinMode with INPUT_PULLUP in setup() before you ever read it.

Buttons change all the time, so you read inside loop(). Each pass grabs a fresh state, keeping your device up to date.

With INPUT_PULLUP the meaning flips: LOW means the button is pressed, and HIGH means it is released. Keep that in mind reading state.

You can't see HIGH or LOW directly, so print it. Sending state to the Serial Monitor lets you watch the value as you press.

Before printing, open the USB channel once in setup with Serial.begin. A common speed is 9600 baud for simple projects.

Upload, open the Serial Monitor, and press the button. You'll see the number jump from 1 to 0 the instant you push it. 🔘

Under the hood HIGH is just 1 and LOW is 0. That is why your printed readings show up as plain 1s and 0s.

You now turn a physical press into a value your code can test. That single reading is the seed of every interactive device you'll build.

Recall what digitalRead hands back to your code.

You used digitalRead in loop() to capture HIGH or LOW, stored it, and printed it over Serial. Next you'll make an LED react to that state. ✅