A thunderstorm is defined by the presence of lightning as there has to be lightning to produce thunder. There are different types of lightning strikes that thunderstorms can produce such as cloud-to-cloud lightning, cloud-to-ground lightning with positive and negative electronic discharge. Positive lightning strikes are often the strongest lightning strikes within the thunderstorm. There is also upper atmospheric lightning called transient luminous events or TLE’s. One type of TLE is called a “Sprite” which occurs high in the atmosphere above the active weather at the surface.
A Sprite is a large-scale electrical discharge which occur high above a thunderstorm cloud, or cumulonimbus, giving rise to a quite varied range of visual shapes. They are triggered by the discharges of positive lightning between the thundercloud and the ground. They normally are colored reddish-orange or greenish-blue, with hanging tendrils below and arcing branches above. They can also be preceded by a reddish halo… This definition and more can be found at Wikipedia.
Blue jets differ from sprites in that they project from the top of the cumulonimbus above a thunderstorm, typically in a narrow cone, to the lowest levels of the ionosphere 40 to 50 km (25 to 30 miles) above the earth. In addition, whereas red sprites tend to be associated with significant lightning strikes, blue jets do not appear to be directly triggered by lightning (they do, however, appear to relate to strong hail activity in thunderstorms). They are also brighter than sprites and, as implied by their name, are blue in color… This definition is also from Wikipedia.
There are different types of Blue Jets called Blue Starters and Gigantic Jets. Elves are another type of TLE which was discovered by the space shuttle.