Is ADD Now Considered A Subtype Of Inattentive ADHD, And Why Has The Term Fallen Out Of Use?

Hi, I was wondering about ADD and ADHD. I seen that ADD is no longer a real Medical Term that s used anymore as of 2019 and i wanted to know if ADD is a subcategory of Inattentive ADHD, or if its still it s own Category. And just some general information on ADD s reasoning for its decline in usage. Thank you!