Stellarium is a software program designed to show the night sky in a 3D simulation. It's an open source project and an excellent choice for anyone who wants to take a good look at the sky and get interested in astronomy.
If you live in a place where it's cloudy a lot, or where you have a lot of light pollution (as most big cities are) so you can't see the stars, this software can help you understand where the constellations are and what the sky looks like in its natural beauty.
But this software isn't only for sitting at home and looking at the stars virtually.
It can also be used outdoors, to coordinate looking at the actual night sky with a telescope. By using the software to locate something you really want to see, and then using those coordinates to find the constellation or other celestial bodies with the telescope, Stellarium is a great tool for astronomers and those who are just interested in the stars.
It's very precise and accurate, so what you see in the 3D simulation is what you're going to be seeing in the sky, as well. This software can help you appreciate everything the sky offers at night and the beauty of it.
There are 32-bit and 64-bit versions available, and the program is versatile, too. In the past, it was more simplistic, but over time it has developed into a very detailed representation of the night sky.
It's feature-rich, offering users options for what they want to look at and the kinds of things that are most important to them. It's easy to use, so even if you're not an astronomer or don't have a lot of experience with the stars, you can still figure this program out quickly so you can get started using it. The fact that it's free just makes it that much better, and you'll likely not find a better astronomy program available today.