Before you head to the salon you should understand the difference between a haircut and a trim. That'll save you and your hairdresser time in deciding what type of hair service you want.
Haircut: A major change that often means a new hairstyle. (For example: from no bangs to bangs, from long to short)
Trim: A minor touch up that keeps your current style and shape. The purpose is to improve hair condition. This usually involves using layering technique to maintain hair texture and snip off any dry or damage hair.
A regular hair trim can extend the life of your current hairstyle and keep it healthy. The cost is usually cheaper (ex: bang trims).