Cis gender, or cis, means that the gender you identify with matches the sex assigned to you at birth. Trans gender is when your gender identity differs from the sex on your birth certificate. In Latin, “cis” means “on this side,” while “trans” means “on the other side.” Cis is not, nor has it ever been, a harmful word.
People who are straight, gay, lesbian, bisexual, asexual, or any other sexuality may still identify themselves as the sex assigned to them at birth. So they would be cisgender. Trans people can be any sexuality as well. Straight trans people could be a trans man dating a woman, or someone who identifies as a woman, and a straight trans woman would be dating a man, or someone who identifies as a man.
Trans can also include people who don’t identify with strict man and woman gender roles. Other people who don’t identify as either male or female call themselves genderqueer or non-binary or just queer, but there are many other terms people use. Don’t use terms like transgendered, transvestite, tranny, sissy, or ladyboi as they’re old-fashioned, slurs, and can be hurtful. No need to think that terms you found in porn are the names trans people want to be called. It’s always best to respect the words people use to describe themselves.
One thing to note: Language changes. Some of the terms now in common usage are different from those used in the past to describe similar ideas, identities and experiences. Some people may continue to use terms that are less commonly used now to describe themselves, and some people may use different terms entirely. What's important is recognizing and respecting people as individuals.
To further expand on the conversation at hand:
Sex refers to a person's biological status and is typically assigned at birth, usually on the basis of external anatomy. Sex is typically categorized as male, female, or intersex.
Gender is often defined as a social construct of norms, behaviors and roles that varies between societies and over time. Gender is often categorized as male, female, or nonbinary. But there are many more ways for it to be labeled.
Gender identity is one's own internal sense of self and their gender, whether that is man, woman, neither or both. Unlike gender expression, gender identity is not outwardly visible to others.
For most people, gender identity aligns with the sex assigned at birth, the American Psychological Association notes. For transgender people, gender identity differs in varying degrees from the sex assigned at birth.
Gender expression is how a person presents gender outwardly, through behavior, clothing, voice or other perceived characteristics. Society identifies these cues as masculine or feminine, although what is considered masculine or feminine changes over time and varies by culture.
One important things to remember about trans people is they just want to be able to live. Get the medical treatment they need. And to have life, liberty, and the pursuit of happiness. If being trans is against your religion, that's for your god to decide when the time comes. If you think its a mental illness, most psychologists, doctors, and medical professionals have decided the best way for them to live is to transition.
If you think that being trans means becoming inherently amoral, or a "groomer", or a predator, keep in mind that any singe person has that capability. And more often than not, a cis person is the one doing those crimes. And it disproportionally is directed at trans people. And more so towards trans people of color.
Any problem you may have about people being trans can be solved by either seeking out the information from reputable sources, or minding your own business. If it doesn't directly affect you, kindly stay out of the way. Everyone should be able to live their lives exactly as they want as long as its not directly, or indirectly, harming another person.
Also, anti-trans laws directly harm cis people too. Restricting the ability to get testosterone or estrogen, when they were designed for cis people, is a problem. Cis people encounter issues where their body may produce less of the hormones they need or none at all, and the only way to fix it is by taking hormones. Cis children who have their puberty start earlier than is safe, have to take puberty blockers. And then they get off them and go through a normal puberty. Any number of reasons for this can happen, such as cancer.
The fact of the matter is, science progresses fast. What you might have learned in school could already be obsolete. 66 years is all it took for humans to go from the first successful airplane flight to landing on the moon. The first flip phone was created in 1996 and the first smart phone was in 2002. With a rapid growth in knowledge and scientific advancements getting faster all the time, gender and our understanding of it can, and has, changed.
Basically what I mean by this is, keep your mind open, be eager to learn new things, and don't just accept something someone says as fact. Even with this post you should fact check and look up peer reviewed studies so you can be sure you are educating yourself on the actual facts and not just taking my word for it.
Albert Einstein once said "Once you stop learning, you start dying." The world is vast and our knowledge of it is constantly expanding. You owe it, not just to yourself, but also everyone around you, to learn and grow and change.
Education is elevation.