Well, a sunspot is not really dark but it is at a lower temperature than the surrounding gases on the surface of the Sun. So it only looks dark by contrast with the area round it.
Sunspots.
They are transitory.
solar flares appear as a dark spot
No. That spot is light and it is day.
The darkest part, where the magnetic field is approximately vertical to the sun's surface is called the Umbra.
A "sunspot."
Sunspots. They are only "cool" relative to the rest of the Sun.
there is about over 10,000,000 sun spots on the sun
Yes I have seen a dark spot on the Sun. It is called a "Sunspot". It is formed on the Sun's surface which is called the "photo-sphere" and is caused by a loop of the Sun's magnetic field poking though the Sun's surface.
Sunspots
Dark spots that appear on the surface of the sun are called sunspots. They are areas of reduced temperature caused by interactions with the sun's magnetic field.
He looked at the sun and observed dark blemishes on its surface, which are now called sunspots. From the movement of these, he was able to determine that the sun has a rotation period of about one month.