Today it is onto star trails which are very different from getting the stars to be static. Similarities are; needing a sturdy tripod, know what you are trying to capture, a foreground interest can make a picture, and planning helps.
Now the differences; a high ISO is not needed, a large aperture is not as important, and a remote release is important. After about 15 seconds or so the stars can be seen as more than a dot. With trails we want that so that is why ISO and a large aperture aren't as big of a deal.
So there are 2 ways to go about star trails. Either taking a bunch or photos and stacking them afterward like above. The benefits are; less noise, if frames have something unwanted (planes, satellites, UFOs, etc) they can be left out. The down side it is time consuming in post.
Below is the other way which is to keep the shutter open for a really long time. I have heard of all night exposures. Personally I have gone with a couple of hours at most with good results. The benefits are it has more of a set it and forget it approach, and post processing is just a couple of images (if combining exposures of a separate foreground and background). The bad part is if something goes across the frame it is a pain if even possible to remove it and there could be more noise from the long exposure.
Experiment and see which you prefer. There are programs that are designed to make the stacking process easier, I just use photoshop because I don't take this type of image often. So find a night sky, grab your tripod, shutter release, camera then go out and shoot.