Third Person:

Third person POV can be the all-knowing viewpoint that gets into the minds of all the characters (frequently used in the past; less used today). That's third person omniscient.

Or third person POV can see the world from just one character's perspective (more used today). That's third person limited.

Either way, the narrative perspective is a bit distanced. It's like the viewpoint is watching events over the shoulder of the character. Here's a section of that example from my middle school novel Iggy's World rewritten in third person limited:

Iggy tested the mike. "One, two, three." Is the mic on the phone working, he wondered? "Check, check." He would have to keep his voice down as his Dad was filming a show right then. Iggy was recording his podcast just off the set.
     "Here we go!" said Iggy, into his phone mic. "Welcome to Iggy's World. I'm your host, Iggy Zambini, and you're listening to epidode one of Iggy's World.

You'll see in this example that, just as you can in first person and second person, you can still listen in to the character's thoughts. It's just that the point of view is standing back a little. To keep Iggy's voice, I used dialogue. That's because the third person POV voice is different from the character's voice.

Third person wasn't right for Iggy's World  because Iggy was recording his story, as it happened, as a podcast. So first person was a much better fit. But I still find third person limited the most versitile point of view and used it in my literary novel The Spawning Grounds, largely because that novel was a multiple POV project. Third person allows for seemless jumps from one character's POV to another. And third person offers that outside perspective which in many ways gives us a deeper understanding of character. Think of it this way: in real life, we often have a clearer perspective on others than we do about ourselves. In the same way, third person allows the reader to step back and view the character with a bit of detachment, to see what they are really about, from the outside. With first person, we're often limited to what the character is willing to reveal, or admit, about themselves.