If you know one thing about batteries, it’s that they have one positive and one negative terminal (or pole). When connecting the battery, the positive side goes to the positive side of a device. Likewise, the negative goes to the negative. The energy won’t flow through the circuit if it’s connected the opposite way. Some components work similarly. But why is that? Because of something called polarity.

This article explains what stepper motors are and how they work. It covers basic motor characteristics, shows how to control a stepper motor using an Arduino and a driver module, and presents a practical project where the motor is controlled with a joystick.

This article explains how PIR motion sensors work, what delay time means, and how to read DOUT/SOUT outputs. It includes an Arduino serial example and an ESP32 WiFi project that hosts a web page and sends an email alert when motion is detected.

This article explains what a breadboard is, how it is built internally, how to use it to connect components, and what its main advantages and limitations are.

This article explains what breakout boards are, how they make small ICs and sensors easier to use, what to check before buying one, and when to choose a breakout board instead of a shield.

This article explains what the CH340 USB-to-serial chip is and provides step-by-step instructions for installing drivers on Windows, macOS, and Linux, including how to verify that the driver is installed correctly.

This article explains what a MOSFET is, how it works, the main types, typical applications, and how to choose the right MOSFET for microcontroller and power projects.

This article explains what LEDs are and how they work. It covers polarity, current and resistors, forward voltage, and different LED types such as bi-color, RGB, infrared, SMD, and OLED, with practical tips for using them in electronics projects.

This article explains what pull-up and pull-down resistors are and why they are used in digital circuits. It shows how they prevent floating inputs, how to connect them with push buttons, how to choose resistor values, and how to use internal pull-up resistors on a microcontroller.

This article explains what the Qwiic system is, how it works, why it simplifies I2C prototyping, how to daisy-chain modules, and how to integrate Qwiic with existing hardware.

The article explains what PWM is and why it is used to simulate analog output with digital signals. It covers cycles, period, frequency, duty cycle, how to calculate duty cycle and average output voltage, and shows an Arduino example that fades an LED using analogWrite.

This article explains what UART is, how it works, what baud rate and frames are, how start, data, parity and stop bits function, and where UART is used in practice.

This article explains what the SPI communication protocol is and how it works. It covers signals like MOSI, MISO, SCLK and CS, explains sending and receiving data, multiple peripheral configurations (regular and daisy-chain), and lists the main advantages, disadvantages and real-world uses of SPI.

This article explains what I2C is, how it works, how devices are addressed, why pull-up resistors are needed, and how to use and troubleshoot I2C in projects.

A Raspberry Pi I2C tutorial using the Qwiic ecosystem. It shows required hardware, how to enable I2C, connect a BME680 sensor and SSD1306 OLED, install tools/libraries, scan devices with i2cdetect, and run a Python example that reads temperature via pigpio and displays it on the OLED.