The smallest stars are known as red dwarfs. They are much smaller and cooler than our Sun, with a mass ranging from about 8% to 50% of the Sun's mass.

Here are some key characteristics of red dwarfs:

* Small size: They are typically only slightly larger than the planet Jupiter, with a radius of about 1/10th that of the Sun.

* Low temperature: Their surface temperatures range from about 2,500 to 3,500 Kelvin, making them appear red.

* Dim luminosity: Red dwarfs are extremely faint, emitting far less light than our Sun.

* Long lifespan: They burn their hydrogen fuel very slowly and have estimated lifespans of trillions of years, much longer than the Sun's lifespan of about 10 billion years.

* Common: Red dwarfs are the most abundant type of star in the Milky Way galaxy, making up about 85% of all stars.

Examples of red dwarfs:

* Proxima Centauri: The closest star to our Sun, located just over 4 light-years away.

* Barnard's Star: Another nearby red dwarf, known for its high proper motion across the sky.

Note: While red dwarfs are the smallest stars we know of, there are even smaller objects called brown dwarfs which are not massive enough to sustain nuclear fusion like stars do. They are often referred to as "failed stars."