The stars we see at night, the ones that can be seen with the naked eye, are they all from the Milky Way or can we see stars from other galaxy.
We can only barely see the Andromeda Galaxy, let alone stars in it, or any other Galaxy.
Right. Even the closest galaxies, such as Andromeda and the Large Magellanic Cloud, are barely “big” enough, in our sky, to be seen as more than a pinpoint of light.
That’s a pretty good username/OP combo too.
Andromeda is much larger in our night sky than what you can see with the unaided eye. This picture shows the scale of Andromeda to the full moon: http://apod.nasa.gov/apod/ap061228.html.
But in the spirt of the OP - with the naked eye we can’t see individual stars in Andromeda. The individual stars in the sky are all in the Milky Way, and all relatively close to Earth.
When I look at pictures of other galaxies, I always see other stars. Are those just in front the galaxy?
And the Sombrero galaxy has what looks like a pretty uniform gas cloud dome. Is that all stars?
Yep, the large stars in those pictures are just stars in the Milky Way that are captured while imaging the deeper galaxy.
It is. The stars themselves are like individual pixels. When you look at the Milky Way in the night sky you might describe it as cloud like. When you look at it with a telescope then you can finally resolve the hazy glow as billions of stars extending towards the center of our Galaxy. It illustrates how vast our Galaxy is and how very very tiny the part we can actually see is.
OK, that is somewhat mind-blowing.
Not exactly. The Andromeda Galaxy, when viewed under a dark sky, appears to the naked eye as a faint gray oval cloud a bit bigger than the full moon. (That’s why it was originally called the Andromeda Nebula - “nebula” is Latin for “cloud”.) The same is true of the Magellanic Clouds, and the Triangulum Galaxy (if your eyes are sharp enough to spot it) - they are all gray cloud-like objects to the naked eye. Our visual acuity is nowhere near good enough to resolve the individual stars that make up the “cloud.” You need a big telescope to do that.
A previous coworker who was an astronomy buff pointed out the merits of his elliptical-ground reflector telescope. It had a great big mirror for a cheap telescope, about a foot IIRC. Being elliptical rather than parabolic, it couldn’t resolve high powers. So I wondered what good it would be. His answer was to gather a lot of light; the night sky is full of big beautiful objects that are simply too dim to see with the naked eye. Evidently, a big elliptical mirror was much cheaper and easier for an amateur to grind than a parabolic.
Unfortunately, I never did get a chance to look through it.
I hadn’t seen the juxtaposition of the moon and Andromeda above. Thanks for posting!
You’re welcome! Andromeda’s even more impressive in binoculars under a dark sky - it covers about 3 degrees of sky (that’s the combined diameter of six full moons!). Everyone should see it at least once in their life. Light pollution utterly kills it, but even under a moderately dark sky it’s a splendid object (even if we can’t resolve the individual stars with our eyes).
The Andromeda Galaxy also has a pair of small elliptical galaxies orbiting it (like our own Magellanic Clouds), which are easily seen in a small telescope. It gives you a really good idea of what our own galaxy would look like if we could view it from outside rather than from inside it.
But there are stars between galaxies, correct? So you could be seeing stars outside the milky way?
I’ve tried looking at it with my telescope. Nope. Not there. Not even close.
I really need to get out of the city.
No, pretty much all stars are found in galaxies. The space between galaxies is very large and very, very empty.
Treat yourself some time to a dark sky vacation. Head off to somewhere very remote and very dark - with your telescope, if possible, with binoculars if not - and see the sky as it was meant to be seen. You’ll be stunned.
Not many. Galaxies provide the environment needed for a star to form and occasionally stars are ejected from galaxies. But intergalactic space is mindbogglingly huge.
Keep in mind that that beautiful picture of a galaxy contains billions upon billions of stars. If you want to imagine what a star would look like at that distance, cut that image of a galaxy into about 10 billion pieces. This is why you can’t see individual stars that far away. If there was a star in intergalactic space halfway between the milky way and that galaxy the star would be about twice as big and still impossible to see. When photographing something so far away as a galaxy the only individual stars you see have to be close.
That being said - there are certain specific types of nova and supernova that can be detected in other galaxies but that’s not what features in the pictures we normally see.
I recently heard an estimate of how many stars there are in the universe. The number is so f’ing huge that I can’t wrap my head around it.
This video gives you a brief tour of the universe. Every dot in there is a galaxy. Prepare to feel small 
Yeah, M31 is an easy naked eye object but you must be under a reasonably dark sky and the higher it is above the horizon the better. Also helps to use averted vision.