The Main Crew
This socially awkward genius has a PhD in physics, loves trains, and refuses to let anyone sit in his spot on the couch
Sheldon Cooper
Sheldon always knocks on a door exactly this many times before saying the person's name
three
Penny works as a waitress at this popular casual dining chain restaurant for the first few seasons
The Cheesecake Factory
The guys spend a lot of their free time and money buying issues at this specific type of retail store
Comic book shop
Penny marries this physicist, even though they break up and get back together multiple times
Leonard
This character is an experimental physicist who marries Penny and tolerates Sheldon as his roommate
Leonard Hofstadter
Sheldon says this specific trademark word whenever he plays a prank or tells a joke
Bazinga
Most of the main characters work at this prestigious California university
Caltech
The characters regularly eat lunch together in this specific campus location at Caltech
The cafeteria
Howard marries this short, high-voiced microbiologist who used to work with Penny
Bernadette
This aspiring actress and waitress lives across the hall from Sheldon and Leonard at the start of the show
Penny
This is the comfort song the characters must sing to Sheldon whenever he is sick
Soft Kitty
Howard is incredibly proud of this achievement, which sent him into orbit outside of Earth
Going into space
When the guys hang out in Sheldon and Leonard's living room, they usually eat this style of food out of white boxes
Takeout
Sheldon eventually marries this neurobiologist who is essentially the female version of him
Amy Farrah Fowler
This aerospace engineer is the only member of the main guy group who does not have a PhD
Howard Wolowitz
Sheldon forces Leonard to sign this massive, legally binding document before they can live together
The Roommate Agreement
Amy Farrah Fowler works in this scientific field, which studies the brain and nervous system
Neuroscience
Penny works at a bar in the later seasons, but early on she pours drinks behind this specific type of counter at her restaurant
The Cheesecake Factory bar
Howard and Bernadette get married on this specific part of the apartment building right before Howard goes to space
The roof
This astrophysicist from India has selective mutism, meaning he cannot speak to women unless he drinks alcohol
Raj Koothrappali
Sheldon is obsessed with this specific mode of transportation and owns a massive model collection
Trains
Bernadette makes a lot of money working for a major company in this industry, which manufactures medicine
Pharmaceuticals
Because this mechanical apartment feature is broken for almost the entire series, the characters always have to walk up the stairs
The elevator
At the very end of the series, Sheldon and Amy travel to Sweden to accept this highly prestigious international award together
The Nobel Prize