There's a lot of misconceptions surrounding BDSM, even within the BDSM community. I will be using myself, and my friends/partners as examples where appropriate.
First off, the actual acronym, and the general concept of it.
From Wikipedia: "BDSM, is derived from the terms bondage and discipline (B&D or B/D), dominance and submission (D&S or D/s), and sadism and masochism (S&M or S/M). BDSM includes a wide spectrum of activities, forms of interpersonal relationships, and distinct subcultures."
People seem to associate BDSM with just the S/m aspect of it, which is only a fraction of the entirety that is BDSM.
People seem to be assuming if you engage in any of this, you engage in all of it. This is of course, silly, as with any part of any sort of relationship, there are variations and differences.
Another common misconception is that engaging in any part of BDSM, will involved someone getting hurt and or abused. Yes, there is a chance someone could be hurt, but education of the topic, and a good level of communication about your desires/limits, will help prevent this.
A great big fat misconception, even among the most avid kinksters is that BDSM is about sex. This doesn't have to be the case, I've known gay men who have been Dominants to lesbians. If that, or the prevalence of other match-ups like that doesn't disprove that BDSM is about sex to you, then I don't know what to tell ya.
For those who say as long as it stays in the bedroom, grow up. People flaunt their relationships all the time in public, what's the difference if someone's in a D/s relationship? You probably wouldn't even notice if you weren't in the know (And if you were knowledgeable about it, you'd probably be into it anyway)
BDSM (The D/s aspect of it specifically) Plays upon the natural Dominant/submissive nature of most people (And a big wave to the switches out there, I didn't forget you) It's basically taking our natural tendencies, and allowing ourselves to present as we'd like, and explore it in whichever way seems SSC (Safe, Sane, Consensual) Be this in the bedroom, in the home, or even in public (Like I said before, you're not likely to even tell it's a D/s relationship from casual observation) My best friend always gets comments on their collar by doctors, store clerks and the like. Not because they may or may not know what it signifies, but because it's a genuinely nice/cute accessory, despite what is represents.
A misconception about D/s relationships is that the submissive(s) have no control, that they have no say in anything, this is just not true, in any healthy relationship, be it business, kinky, or vanilla involves communication about what is desired out of it, and what they expect. A submissive person may be willing to submit to their Dominant, but that doesn't mean they give up their basic human rights to them (although, one totally could) With any sort of healthy BDSM relationship, there are safeguards, in the form of safewords, or similar practices. If the people involved are respectful of eachother's safety, the action will stop. As people have previously mentioned in this thread, it really does put the submissive in control in a sense (assuming it's a healthy relationship)
Actually, now that I think about it, most misconceptions of BDSM are based off of unhealthy representations of them (which I blame the media for) A healthy BDSM relationship can actually be SAFER than a vanilla one, as there has to be a hell of a lot more communication going on, and you HAVE to respect your partner(s) safety. Kinksters network well, and if someone's not playing nice, the whole community might know to veer away from them.
When it comes to S/m relationships, there's actually a few branches of it, physical S/m and emotional/psychological S/m. The physical one should be pretty self-explanatory, it involves vigorous stimulation of the masochist while aroused (This part is important, the while aroused part) The human body, while aroused can receive stimulation that would normally be unpleasant, or even painful, but it's now perceived as pleasure, extremely intensely in some people. This is entirely natural, and in my opinion is actually a survival mechanism from back in Monkey Times. Women giving birth can often recognize this, while giving birth naturally, the position of the baby inside often stimulates the G-spot, which leads to stimulation, and can make the whole process a lot less unpleasant. This has been attributed to the "high" women feel after this (Also, haha, many of you got your mom off, I saw via C-section myself)
Emotional S/m is a whole 'nother kettle of fish really, and like anything pertaining to the human mind, isn't all that understood. I honestly cannot provide much info on this, despite being an emotional masochist myself. All I can say is that some people just like to be mistreated.
With both of these forms of S/m (and any form of BDSM) it is very importiant to practice "aftercare"
From the Wipipedia: (Clever bunch we kinksters are eh?) "Aftercare refers to the special attention given to a bottom or bondage victim after a scene.
The intensity of emotion and the physical demands put upon the submissive can be extreme (which may be one of the attractions to BDSM for them) and careful attention is often needed to help them settle back to a more normal state.
If they have been in stringent or prolonged bondage, or have been flogged, they may have aching muscles or skin marks that require attention. Long periods of sensory deprivation may lead to disorientation.
Often, the first thing they will need is a drink of water, followed by a trip to the toilet. Lots of tender affection, cuddling and kissing will often comfort the person and improve their mental state. "
This is of course to ensure health, and a fulfilling experience for the people involved, as well as restoring one's sense of humanity (As this can often come into play in some of the more heated practices)
The reason I left the B/D part for last, is because I feel it ties in with the other parts of BDSM. Bondage for one can be used alone, which can be a helluva lot of fun in itself, even vanilla people practice this sometimes (fuzzy handcuffs anyone?) but it is often used with the D/s and S/m areas either to add to, via the interesting dynamic bondage entails, or enhance via the restraining aspect of it. (Personally, the more helpless I feel during a scene, the better) Which ties into whole D/s S/m bits very nicely (Just use your imagination people, you're on the internet, nothing is sacred anymore)
Discipline, like emotional masochism (they're quite related really) Can arise from, and be explored in many different ways. And like bondage, it can work stand alone, or be used to enhance the experience of other bits and pieces of BDSM.
I wish I could of covered more of this, but I'm no expert, and I've got stuff to do. I hope this submissive, zany, kinky, masochistic, pansexual transsexual has provided some insight into all of this (and not caused further confusion) There's tons of resources online you could look up if you're curious (Like the Wipipedia I mentioned)
Kinksters are just human sexuality/psychology nerds/geeks, we just know more about human sexuality than most, we're not monsters.
Have a good one, and stay away from the Goreans, that's not true BDSM, and it's often extremely sexist/homophobic/harmful