Use of validation set

Hey guys. I’m having a hard time understanding how and where to use the validation dataset since most of the examples I’ve seen here have only train and test dataset. I am trying to implement sentiment analysis using tensorflow and following the huggingface tutorials but I can’t find the use of validation set. All I found is that it is being used in the model fitting. Is it all there is?

Sorry if the question is so basic or has been answered, I am still learning. Thank you for your time.