| analog |
A varying signal (0–5V), read as 0–1023 on the Uno |
| baud |
Serial speed in symbols/second — both ends must match |
| breadboard |
Solderless prototyping board; holes in rows of 5 connect |
| bootloader |
The program on the chip that receives your uploads |
| debounce |
Ignoring a button's contact bounce so one press counts once |
| digital |
Two states only: HIGH (5V) or LOW (0V) |
| GND |
Ground — the 0V reference everything measures against |
| IDE |
Integrated Development Environment — the Arduino programming app |
| INPUT_PULLUP |
Pin mode using the chip's internal pull-up resistor (idle = HIGH) |
| library |
Someone else's packaged code you include with #include |
| loop() |
Runs over and over forever — your program's heartbeat |
| microcontroller |
A tiny computer (processor + memory + pins) running one program |
| pinMode() |
Configures a pin as INPUT, OUTPUT, or INPUT_PULLUP |
| PWM |
Pulse Width Modulation — rapid on/off flicker that fakes analog output |
| Serial Monitor |
The IDE window showing what the Arduino prints |
| setup() |
Runs once at power-on/reset — configuration goes here |
| shield |
A daughterboard that plugs onto the Arduino (motor shield, etc.) |
| sketch |
An Arduino program |
| VCC / 5V |
The positive power supply pins |