The vast majority of the meteors you see at night are actually smaller than a grain of sand. However, several hundred tons of meteors burn up in the atmosphere every day.
Most meteors are yellowish or white, with the color depending on how bright they are (your eyes have a hard time discerning color in faint objects) and how hot they get. Some extremely bright meteors can appear blue or white.
The intensity of the meteor depends on how hot it gets, how big it is (a bigger meteor can generate more energy because there is more material to heat up), and how fast it is coming.
The length of the trail the meteor leaves on the sky depends mostly on viewing angle: If the meteor is coming across your line of sight you might see a long trail, but if it is coming straight at you, you won’t see any trail at all (and you’d better hope the meteor burns up!). — PHIL PLAIT, ADVANCED COMPUTER GRAPHICS, INC.