IN/OUT
- Integrated LED stat

This bloc will control the internal LED of the NODEMCU. (Video)
- Digital write

Write a HIGH or a LOW value to a digital pin. (Video)Example: blinking an LED connected to the port D0

- Digital read

Reads the value from a specified digital pin, either HIGH or LOW.
(Video)
- Analog read:

Reads the value from the specified analog pin. The NODEMCU has only one analog pin. It will map input voltages between 0 and 5 volts into integer values between 0 and 1023.
(Video)
- Analog write:
Writes an analog value (PWM wave) to a pin. Can be used to light a LED at varying brightnesses or drive a motor at various speeds. The value parameter could be from 0 to 1023.
Video: PWM

High – Low:
Will return 1 you choose High or 0 if you choose Low.