Learn more here.
Valid until end of May, read more here.
I’m taking two professional certifications there now, almost done with the first one. Will do a review when completed.
Try old chatbots like Eliza and Mitsuku, Sentence Generator, Thing Translator, Emoji Scavenger Hunt, Quick Draw, Shadow Art, Intelligent piece of paper, Semi-conductor, or Freddiemeter. Have fun trying a few, see his informative article here.