Exam gloves provide a barrier between rescuer and victim. Exam gloves come in three common types: latex, nitrile, and vinyl. Many people develop allergies to the protein found in latex and cannot wear latex as a result. Nitrile and vinyl are much more hypoallergenic and provide a non-latex option for those with latex allergies or sensitivities.
Gloves come in four or five different sizes. The most common are small, medium, large, and extra-large. Extra small can sometimes be found, but the availability is inconsistant.
Latex gloves are usually regarded as the most comfortable, but users may develop allergies to natural protein in the latex.
Nitrile gloves have the next best feel and functionality to latex, but in rare cases, can also lead rescuers to develop allergies. Overall, for people with sensitivity to latex, nitrile is probably the best option.
Vinyl gloves are those weird gloves the cafeteria workers used in high school. They do not stretch and are very uncomfortable. However, vinyl gloves are the most hypoallergenic of the three types.