Photographers have such a unique taste on life. Each shot they take they pre think it in their head but they also envision the aesthetic. In the photography world we have the ability to capture all motion of life whether it is a time lapse of the milky way or capturing the speed of a bullet. You always hear in movies "What if we had the ability to control time?" Well.... in a sense we do...
So, what is shutter speed? Shutter speed is the time it takes for the shutter curtain to open and close in front of the censor. The censor in your camera, whether this is a DSLR or an iPhone, has a piece of beauty inside it that captures the image and records it to the memory card. In front of that censor is a curtain blocking it from all light until it is released, depending on how long it is open for determines the shutter speed.
Now I personally get all jittery when I hear my shutter speed bursting loud at 1/8000th of a second. But that's just me, before we get into all the cool things let's talk about the scale of shutter speed so you can make magic in the world. Shutter Speed is timed, just like a clock or watch, but just in a different form. Shutter Speed is measured in seconds or fractions of a second, make sense? For instance if you're to scale back your shutter speed all the way, by default your camera would let you take a 30 second exposure, it would look like this...30", the 30 stands for thirty and the " stands for seconds, make sense? As long as you know that we can move forward, as you begin dialing your shutter faster you will run into a number that looks like this 1/1. This means you have entered the "second" mark and this stands for one whole second. From here on faster is a fraction of that 1 second. For instance, you keep getting faster and stumble upon a number that may look like 1/200. This means out of that 1 second, only a 200th of that second is being captured, now that is pretty fast I would say.
I am a Wedding Photographer. I typically shoot quite fast, from a shutter speed of 1/200th up to 1/8000th of a second. Now that is a wide variety of different speeds I am capturing, but once you hit the 1/200th mark, that is freezing motion, if you get motion blur in your shot with a shutter speed like that, it is usually the weight of your lens or your hand is moving quite rapidly. So I can shoot anywhere from that range and be just fine, as long as it is exposed properly that is perfection. Now if you are shooting anything slower then that, below the 1/200th shutter speed, and depending on the lens you have I would consider using a tripod, this is only recommended if you are shooting nature/landscape. Another thing to consider is my rule of thumb (not that I created it but no one has ever told me) when it comes to shutter speeds and lenses of choice. Since I use a couple different types of lenses I can brake the rules sometimes, remember all rules are made to be broken in photography...but say I am using a fixed 50mm lens, I am shooting wide open with an aperture of 1.4, but it is still quite dark, I can take my shutter speed and drag it all the way down until it hits 1/50th of a second. I can do this because the weight of that lens and my hand movement, if I'm being steady, will allow me to take a shot and have slim chances of motion blur, now, this is an "only if you need to type thing" for instance when I shoot at concert venues, it is very dark and I need as much light as possible. But the rule of thumb was depending on the lens you have, for instance a fixed 50mm you can shoot at shutter speed of 1/50th, if you have a 70-200mm lens, you can get away with shooting at 1/200th, if you have a 24-70mm lens, you can get away with shooting at 1/80th of a second, now this is all in correlation with your aperture as well and making sure you are properly exposed. Make sense? Maybe not but it will if you keep shooting.
Shutter Speed is a precious thing... It is one of three pillars in photography, the other being aperture and ISO. Now granted, all these three pillars coincide with one another, they all need to be in sync (not nsync) with one another in order to get your specific shot, please I encourage you to not just press down the shutter and be like "Whatever happens happens." The world is an empty canvas and you are the artist.