Traits are the characteristics of survivors reflecting their personalities, backgrounds, hobbies, talents and history. These are unique and sometimes can give a personal skill to a character, effectively starting the survivor with free stars on that particular skill tree.
Some other aspects of traits which affects survivors includes how fast or how slow they can develop a certain skill, the way they interact to other characters, and unique gameplay changes, like the Powerhouse and Reflexes unique movesets.
Traits are permanent and cannot be changed, however they can be gained though by clearing side missions or through telling each other life stories while working on a mission together.
Here is a list of currently known traits:
Accountant
Aikido
American Idol Fan
A Pack A Day
Architect
Army Medic
Asthma Attacks
Autocrat
Bad Back
Born Leader
Braggart
Brute
Bum Knee
Carpenter
Caterer
Chatterbox
Chronic Fatigue
Clerk
Cop
Cosplayed
Coward
Cycling
Daydreamer
Dentist
Dim Bulb
Doctor
Drunk
Eagle-Eyed
Eccentric
Enjoyed Antiquing
Enjoyed Camping
Electrician
Engineer
Father Figure
Flirt
Funeral Director
Gallery Owner
Glutton
Gossip
Got the Watch
Great Reflexes
Grocer
Hates Gore
Hiking
Historian
Homebody
Iconoclast
Kind
Knitting
Liked Range Shooting
Liked to Hunt
Liked to Travel
Live a Little
Lost Brother
Loved Books
Loved Cycling
Loved Hiking
Loved "Idol"
Loved Literature
Loved Movies
Marked for Greatness
Mechanic
Movies
Natural Athlete
Nimble
No Nonsense
Off the Wagon
Organizer
Online Shopper
Paramedic
People Person
People are Strange
Played Golf
Played Trivia Games
Practiced Photography
Practiced Taxidermy
Preacher
Presence
Problem Solver
Psychopath
Reading
Scary Santa
Self-Sufficient
Selfish A**hole
Service Job
Sleaze
Soldier
Strong as an Ox
Student
Studied Boxing
Stylist
Team Player
TMI
Total Lush
Travel
Trumbull Local