Raspberry Pi without burning the pins (LED, Servo, Solenoid+Relay, DS18B20)

Raspberry Pi GPIO tutorial for beginners. Raspberry Pi GPIO pinout: physical pin vs BCM. How to wire an LED to Raspberry Pi GPIO with a 330 ohm resistor. Hardware PWM on Raspberry Pi. SG90 servo on Raspberry Pi GPIO, power from the 5 V pin only for an unloaded demo. DS18B20 on Raspberry Pi, 1-Wire temperature sensor. Solenoid valve on Raspberry Pi through a relay, not straight from a GPIO pin. Pinctrl on Raspberry Pi OS. Why a motor or a coil needs an external supply. How to control Raspberry Pi GPIO through bash. 0:27 Theory 2:15 LED(on/off+PWM) 8:32 Servo (PWM) 11:26 Temperature Sensor (DS18B20) 14:46 Solenoid valve & Relay