His character Leonard is often considered (but not confirmed or declared) the central protagonist of the series because of his Only Sane Man quality and being the show's biggest Butt-Monkey by far. Leonard can be considered more of a protagonist than Penny and Sheldon can, as the latter two are always exploiting Leonard for servitude, money, emotional support and self-esteem. They also sometimes just bully/pick on Leonard with malicious insults.
Galecki is currently one of the highest-paid live-action TV stars in the world. He made headlines back in 2014 along with co-stars Kaley Cuoco and Jim Parsons when they fell into pay disputes with the network as they all demanded at least $1 million per TBBT episode. The core three were actually all making hefty salaries compared to the vast majority of live-action sitcom stars at $350,000 per episode as while most live-action TV actors make low 5-digits per episode (around $15,000 to $30,000). This can mostly be explained by TBBT performing much better financially than most American television shows at the time. Galecki, Cuoco and Parsons refused to accept their salary as it is and successfully secured a pay raise to $1,000,000 and even more backend money. Supporting actor Mayim Bialik decried the pay disputes and said the show's stars including herself are all overpaid (although Bialik never took pay cuts after making those comments and even accepted pay raises in 2018).
Galecki pursues work outside TBBT to fund his lavish lifestyle such as his $9 million home in Hollywood Hills. Aside from being in a sitcom, Galecki has been in darker-toned movies such as Rings and The Cleanse in a slight case of Tom Hanks Syndrome.
After the Roseanne revival was cancelled by ABC following the lead star's allegedly racist comments on Twitter, Galecki made a return in the spin-off show The Conners.
- Galecki holds liberal views, is a supporter of the Democratic Party and endorsed both Barack Obama and Hillary Clinton's presidential campaigns.
- While his character Leonard is fond of meat dishes, Galecki is a vegetarian much like his TBBT co-stars Cuoco and Bialik. However, Kevin Sussman (Stuart's actor) is even thinner than Galecki is.
- Galecki once was a smoker, but he quit before Season 8 of TBBT.
- Back in the 2007-2008 TV Strikes, Galecki was the only member of TBBT's main cast to decline participating in the strike.
- In spite of his character Leonard being a CalTech physicist, Galecki never attended a college.