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Understanding the Differences

Sex

Sex describes one’s physical-self at birth. 
Many people consider sex as binary: either male or female. That is a fundamental concept which is based on what’s between a person’s legs. It is common misconception that the sex of an infant is determined by their genetelia and genetelia only but, in reality and in many cases, the genital of the infant isn’t always a penis or a vagina. Due to imbalance in the sex chromosomes and internal reproductive organs, the external genital consists of something other than a general penis or a general vagina; such babies are assigned the sex called ‘Intersex’ right after birth because they don’t aptly fit into what we stipulate as male or female. 
So, sex is abour your body. 

Gender

Gender is what people feel and express themselves as.
Unlike sex, gender is social and psychological. We have been taught that male or female are the only genders but again, that is a ‘binary’ view of gender. One may be male physically, but feel more comfortable thinking of oneself as a female; and vice versa. Gender has two characteristics, both of which will help us further sharpen our understanding of this domain:

Gender Identity:  A term for how a person self-identifies in terms of being a man or woman or both or neither or somewhere in the middle or another gender generally. Some examples are jotted below:

• Cisgender: Someone whose gender identity matches with thier birth-assigned sex (e.g: a cisgender man is someone who was assigned as male after birth and identifies as a man now, too.)
• Transgender: Someone whose gender identity differs with their birth-assigned sex (e.g: a transgender man is someone who was assigned as female after birth but now identifies as a man.)
• Non-binary: Someone whose gender identity doesn’t harmonize with the traditional ‘male or female’ societial model (e.g: a male who does not want to be labelled as a male and not a female either.)
• Genderfluid: Someone whose gender identity is not fixed but varies with time and situation (e.g: they might identify as a man one day and a woman the next day or agender or bigender, etc. This may be a way to explore gender before landing on a more stable gender identity or may continue indefinitely as part of one’s life), etc.
• Gender Expression: The gender one chooses to present oneself to the world. It is the way a person conveys their own gender. Expression is related to one’s appearance (clothings, hairstyle, makeup, etc) and mannerism (speech and behaviour), consistent with their gender identity. For example: a Transgender individual might express their gender through Drag; having long hair and wearing dresses are typically considered feminine expression; having muscular body and shorter hair are considered masucline expression, etc. 

Sexuality 
Sexualilty refers to whom you are attracted to sexually. 
A person’s sexuality, or sexual orientation, determines whom they do or do not feel sexual and/or romantic attraction toward. Below are the definitions of a few sexualities: 

• Heterosexual (Straight): An individual who is attracted to people of the opposite sex. 
• Homosexual (Gay and Lesbian): An individual who is attracted to people of the same gender as their own. 
• Bisexual: An individual who is attracted to both men and women. 
• Pansexual: An individual who is attracted to all sexes and genders in the spectrum.
• Asexual: An individual who does not experience sexual attraction at all, etc.

What are Gender Pronouns and why are they important?

For as far back as we can remember, gender pronouns have come reluctantly to us and that happens because he, she, him and her were embedded into our system since childhood. But this binary view of pronouns has caused unintended repercussions in the lives of many LGBTQ+ members; specifically Transgenders and Non-binaries.

Gender pronouns are words that people use to refer to others without using their names. Most of the queer people grew up to a system that subscribes to the toxic Binary view of genders (male and female, nothing else) which clashed with their gender identity. So, gender pronouns were introduced so as to sanction their own identity because other than their names, it is how they are identified. 

Also, it is essential to understand that it is Gender, not the assigned Sex, that determines the pronouns of a person and as aforementioned, since Gender Identity is the internal sense of an individual, it is practically impossible to know what pronouns are most appropriate without asking, which is why I can not, and will not, suggest what stereotypical pronouns to apply for what gender. 
However, I did list some suggestions to keep in mind when you are interacting with anyone and keen/confused about their Gender Identity, Sexual Orientation and/or Gender pronoun:

• Begin any sort of introduction, whether it be meeting or casual banter, by asking everyone to share their pronouns. 
• Never assume. Because even if your assumptions turn out to be right, the Gender Identity spectrum and the variation of experiences do not end at it. Not to mention, assumptions can cause discomfort. 
• Always ask politely and make sure they are comfortable enough to share their identity and pronouns with you. 
• Use gender-neutral pronouns and words if confused (E.g: they/them; replace  boyfriend/girlfriend with partner; brother/sister with sibling, etc)
• Make genuine efforts to understand rather than fussing about the broadness of it all. Imagine if someone called you by a different name rather than your real name - multiple times - despite your request not to do so. It’d be mentally draining to go through such an experience. 
• Unlearn the notion of gender, sex and sexuality being only binary. 
• It is okay to make mistakes. Afterall, everyone learns from their setbacks.
• But, it is not okay to repeat them again and again. 

Misgendering a person by using an incorrect pronoun is, in every sense, an act of disrespect. You are not only denying them their personhood but also creating a false identity for them. How they express their gender might not always align with their actual gender identity and therefore does not grant us the right to take their identity for granted. Using a person's correct pronouns fosters an inclusive environment and ratifies a person's gender identity and, more than anything, exhibits that you validate and care for their identity. It is, therefore, colossally important to keep up with this domain of the LGBTQ+ community and to realize that it is not ‘Preferred pronoun'. It is not a preference, it never has been. It is just who they are and always have been.