The Slider widget allows you to send a specific range of values from your Blynk app to the hardware (Raspberry Pi). It is analogous to a potentiometer in electronics. The default value of the Slider widget provides a value range of 0 to 255. As examples, sliders can be used to control the brightness of an LED or to control a servo motor.
In this example project, you will control the brightness of an LED attached to the Raspberry Pi BCM_GPIO pin 18, which is a Pulse Width Modulation (PWM) pin.
Brightness can be changed by analog or PWM. With analog, you can control the brightness by simply adjusting the DC current in the wire. But with PWM, you can change the brightness by varying the duty cycle of a constant current in the wire. Therefore, PWM can be implemented on any digital pin without using a potentiometer to control the current flow. PWM is the most appropriate method...