To be able to talk about something you started in the past and continuing to do

Today's Phrases
What have you been doing all day?
I've been looking for the missing boy.
We use the Present Perfect Continuous tense to show that something started in the past and has continued up until now. "For half an hour," "for six months," and "since October" are examples of durations which can be used with the Present Perfect Continuous.

You can also use the Present Perfect Continuous tense without a specific duration.
Without the duration, the tense has a more general meaning of "lately." We often use the words "lately" or "recently" to emphasize this meaning.