Most of us would identify as an introvert or an extrovert. You may even have taken a test which told you which you are. These terms can be useful to understand and discuss preferences, but they are often both overused and misused.
Being an introvert or extrovert isn't about whether you prefer to be at a party or at home with a book. It's about where you get your energy from - what you can find tiring and what replenishes you. Typically, extroverts will be energised by a group of people around them, while introverts will recharge by spending time alone, or with one or two others.
The idea of a dichotomy is alluring, but the reality is that we are all somewhere on a spectrum. Our levels of introversion or extroversion will fluctuate depending on our mood, situation, age or any one of many other factors.
Lately, the concept of an "ambivert" has become more mainstream - referring to someone who can switch between introversion and extroversion. There are many benefits to this, particularly as a leader, because you can adapt to different situations and relate to different people.
But I'd always be cautious of putting a label on yourself, or anyone else. You will know what your preferences tend to be, but people who are consistently one extreme or another are incredibly rare.
It makes more sense to use these concepts to check in on yourself, what you're doing and what your needs are. Ask yourself:
What energy do I need to bring to this situation? Should I be talking or listening?
What energy does this person need from me?
What will energise / replenish me today?
How is the balance between social and quiet time working for me at the moment? Do I want or need to make any changes?