Most karate styles use a ranking system in which lighter colored belts are worn by beginners and darker colored belts are worn by the experts, with white as the lowest ranking and black as the highest. Many schools also use striped belts that represent the student's progress from their current belt to the next, with more stripes added on as the student progresses.
Many karate schools follow a ranking system in which students must progress through many levels of basic training known as kyu and then progress through expert level training known as dan. Beginners at the lowest levels of kyu are usually assigned white belts, while black belts are usually given to those who have achieved dan levels. The exact belt color order differs depending on the style of karate, but oftentimes there is not even a uniform belt order between dojos of the same style.
The stripes used on belts are usually either white or the color of the next belt in the student's progression, so if the belt order goes from white to yellow and the student is wearing a white belt, then the student receives yellow tips. Many dojos use white and red stripes on a black belt to signify the student's progress through the dan.