Fans of the long-running science fiction TV Show Doctor Who know that the titular Doctor is a man (and now woman, too) of many faces. Many actors have portrayed this character, who changes form once every few seasons. From William Hartnell to Tom Baker to David Tennant to Jodie Whittaker, many of Britain’s favorite stars have brought this character to life.

But the change is more than skin-deep. Each Doctor has a different outfit, different TARDIS, different companions, and a different outlook on the universe and their own selves. Two of the most popular Doctors of the current series is the 10th, played by David Tennant, and the 11th, played by Matt Smith. So, which one is the best, and why?

10th Doctor: Breakthrough Doctor

There is a reason to love every incarnation of the Doctor, but based on fan reactions, the 10th was the breakout Doctor for the new series (2005 to present). Christopher Eccleston was the 9th Doctor to launch this reboot, but things really got good when David Tennant took over.

Even now, many fans consider Ten to be the definitive Doctor of the current era, against which all the others are compared. He’s the new version of the famed 4th Doctor, who had a long run (1974-1981). That’s saying a lot.

11th Doctor: Youthful Energy

When Matt Smith was cast as the 11th Doctor, he was 27 years old, making him the youngest actor to ever play this character. True, Peter Davison (5th Doctor) was a bit youthful too, but Eleven really brought on the boyish charm.

Eleven is older than Ten, but he looks and acts younger, and he pulls this off without seeming immature or annoying at all. That’s tricky, but it worked, and Eleven often fooled his enemies (and sometimes his allies) into underestimating him. He’s a pretty athletic guy, too. All this contrasts him sharpy with the 1st, 3rd, and 12th Doctors in particular.

10th Doctor: Many Companions

The 10th Doctor inherited Rose Tyler from the 9th, and that included Mickey Smith and Jackie Tyler, too. Then, Ten met Martha Jones, who proved a great companion, and then Donna, who was a total firecracker who could easily keep up with Ten’s antics.

All these companions gave Ten a lot of people to talk to and go on adventures with, and we could see many different sides of his personality by having all these varied companions. He certainly acted differently around Rose and Martha as compared to Donna, and in a good way. Each companion brings out the best in him.

11th Doctor: Great Screwdriver

The 10th Doctor also inherited the 9th’s sonic screwdriver, but it was a bit meh. That little screwdriver was a bit plain and seemed a bit silly after a time. And it broke right as the Doctor regenerated.

Now, the 11th Doctor brings us a bigger, cooler screwdriver with classy brass colors and vivid green lights. It can also extend pretty far, and its prongs can split open to collect readings on the Doctor’s surroundings. It’s one cool prop, that’s for sure.

10th Doctor: Fought The Master

Who is the Doctor’s greatest enemy? The Daleks? The cybermen? His own hubris? Arguably, his greatest villain of all is The Master, another rogue Time Lord who escaped Gallifrey’s fate.

The Master was a cartoony villain in the old series, but he’s back and better than ever now, and the 10th Doctor faced him in the revival series’ third season and in The End of Time. Their battles were legendary, and the Doctor saved all of humanity from The Master’s plot to convert everyone into copies of himself.

11th Doctor: Reset The Universe

At some point, the 11th Doctor went to Stonehenge, and what he found there was remarkable: a solid stone box known as the Pandorica. We had every reason to think that the Pandorica was serious trouble.

The Doctor was sealed in once his united enemies cornered him, and to make a long story short, Eleven reset the entire universe with the TARDIS’ power and put everything right. Not even his combined enemies can stop him!

10th Doctor: Love Story

This is Rose Tyler, the 9th Doctor’s only companion and the 10th’s first. For the most part, the Doctor doesn’t get romantically involved with people, but there was something special about the girl named Rose Tyler.

By the end of the second season, the 10th Doctor was ready to say “I love you,” (we are pretty sure of that), but the two of them tragically forced apart to prevent the destruction of reality as we know it. Remember Bad Wolf beach? We do, too.

11th Doctor: Victory Over The Silence

This was a remarkable story in the 11th Doctor’s arc. At some point, he was called to the United States in the late 1960s, and he got tangled up in a shadowy scheme to murder him and keep humanity in the thrall of the Silence.

But not so fast. The 11th Doctor (with help) escaped his own death, investigated the insidious Silence creatures, and used the publicity of the famed moon landings to expose them, and make them the #1 enemy of humanity for all time. The Silence will never terrorize humanity again, thanks to this Doctor.

10th Doctor: Cool Debut

The 10th Doctor briefly appeared in “The Parting of the Ways,” but he really had his first adventure in a Christmas special. He spent most of the episode in bed, recovering from regeneration.

Then the Sycorax invaded, and threatened to kill off over a billion people if their demands weren’t met. But then Ten sprang into action (in pajamas and a robe), took up a sword, called the Sycorax’s bluff, defeated the leader, and accidentally quotes The Lion King all in one go. Not a bad way to launch his career!

11th Doctor: He Regenerated Happy

For the most part, the Doctor does not enjoy regenerating. The 2nd Doctor was forced to regenerate right before his exile, and the 8th Doctor woke up confused and in pain. But the 11th had a much better time of it.

Eleven expected to die at Trenzalore, but he survived, and he was pretty grateful for Clara’s help. He discarded his bow tie and his current identity without regret, and he fondly said: “I will always remember when the Doctor was me.” Overall, Clara was much more anxious about the regeneration than he was.