Brightness of the LED's

In this video( https://trainings.boltiot.com/courses/429176/lectures/6654269)
we were talking about the brightness of LED’s so how analog signals help in the case of brightness of the LED’s through the Analog pin?

You can set the output voltage of analog pins by passing different values in the function analogWrite(pin_number, analog_value);. Here analog_value is the value between 0-255 a, 0 will produce 0v at the output and a 255 will produce 3.3v at the output.
This analogWrite() function can work with gpio pins of bolt module.
Please note that the A0 pin is for input purpose not for output , you can’t connect a led or any thing related to output there.
You will learn about this—>analogWrite() in upcoming portion.

analogwrite(pin num, output value)
analogwrite=>sends analog value to some pin
ouput value=>varies between 0 to 255
pin num=>any analog pin
where the value
0=0v(0%)
255=>5v(100%)
nearly168=>3.3v
it is able to send an analog value by using a process called PWM -( in order to use pin as a digital pin ) it generates PMW signal