Sunspots appear as dark spots on the sun. They tend to follow an eleven year cycle from solar minimum, a time of low sunspot numbers, to solar maximum, a time of high solar numbers. Sunspots are darker because they are cooler because the strong magnetic fields inhibit the transport of heat by the convective motion of the sun. Sunspots are usually located near the solar equator, but never below 5 or above 40 degrees north and south latitude. Sunspots themselves do not seem to have an effect on the Earth but they do seem to correlate with an increase in activity on the sun that does.
Solar flares occur in the chromosphere and are associated with regions of sunspot activity.
Click here for an image of a solar flare. During solar maximum, solar flares occur at an average of one flare per week. The flares can last for hours for large events to only tens of seconds for impulsive events. A solar flare heats the solar gases to tens of millions of degrees Kelvin and accelerate protons and electrons streaming toward Earth. The abrupt release of energy contains ultraviolet light, x-radiation, and sometimes gamma radiation.