Sex refers to biological traits. These include chromosomes, hormones, and sexual anatomy. Sexual anatomy includes body parts such as a penis or vagina.¹ Sex is a label usually given to a person when they are born based on their body characteristics.

Gender is shaped by social factors. Gender roles, expressions, and identities vary across cultures. Gender identity is about how people feel on the inside. A person may feel like a boy/man or a girl/woman, or they might feel like neither or both.^2,3 There are many ways to describe what gender is. Different people and places around the world have different expectations and ideas about gender.² These social and cultural understandings of gender can change over time.²

Sex and gender are widely understood to be different concepts. Sometimes, a person's gender matches what is expected in a society or culture based on the sex assigned to them at birth (e.g., cisgender) and sometimes it does not (e.g., transgender, non-binary).⁴ The distinction helps us better understand the difference between the concepts of sex and gender.⁵

There are more than two genders. Binary refers to the existence of only two categories. Sometimes these categories are seen as opposite. While gender is often thought of as binary, with only two options of boy/man and girl/woman, there are many more genders.²

People may have binary genders, nonbinary genders, more than one gender, or no gender at all. Binary genders are girl/woman and boy/man. Cisgender and transgender people can have binary genders.⁵ Non-binary genders include gender fluid, genderqueer, and many other genders.^6,7 Indigenous people may identify as Two-Spirit or Indigiqueer, although these identities are not the same as non-Indigenous genders.⁸

Over 40,000 Canadians identified as nonbinary on the 2021 census.⁹

While it is often thought that sex is binary, there are more than two sexes. Sex is often put into two categories: male and female. Intersex, or differences in sex development, indicates when a person's body does not fit the typical expectations of male or female bodies.¹⁰

Intersex, or differences in sex development, describes many variations of sex beyond male and female. People may be born with combinations of internal and external body parts and hormones different from those typically seen in females and males. There are several different combinations of sex chromosomes (X and Y). These and other biological differences naturally occur among humans, resulting in differences in sex development.

It is estimated that up to 1.7% of people are intersex or have differences in sex development.^10,11 Some people may not be aware that they are intersex until puberty or later in life. Some people may never know.