A pickguard (also known as scratchplate) is a piece of plastic or other (often laminated) material that is placed on the body of a guitar, mandolin or similar plucked string instrument. The main purpose of the pickguard is to protect the guitar's finish from being scratched by the guitar pick.
A prep cook is someone that assists the cook in preparing and serving of items on the menu. His/her job description involves various kitchen tasks like general cleaning, dish washing, and storing of food and other items in their proper positions.
In most professional kitchens, there is a chain of command which goes from executive chef to head chef to sous chef and finally to a station cook or chef de partie, otherwise known as a line cook. A line cook prepares a limited number of food items according to the orders of a supervising sous chef. This may involve working at a meat station, a garnish station, a fry station, a cold salad station or a number of other compartmentalized food prep areas. A professional line cook should know how to work each station in the kitchen, including prep work and coordination with other stations and the head chef.