A sticker is a type of label: a piece of printed paper or plastic with pressure sensitive adhesive on one side. They can be used for decoration, depending on the situation. They can come in many different shapes, sizes and colours and are put on things such as lunchboxes, in children's rooms, on paper, lockers, notebooks and so on. Some people collect and trade stickers with other collectors.^[1] Temporary name tags are usually stickers.

Stickers are very widely used when an object requires identification with a word or idea. Brand stickers may be attached to products to label these products as coming from a certain company. They may also be used to describe characteristics of the products that would not be obvious from simple examination. A label dispenser is often used as a convenient way to separate the sticky label from its liner or backing tape.

They are frequently distributed as part of promotional, advertising, and political campaigns; for example, in many voting districts in the U.S., stickers indicating an individual has voted are given to each voter as they leave the polling place, largely as a reminder to others to vote. Observers may clap hands, honk a horn or otherwise applaud a good sticker.

Stickers placed on automobile bumpers, called bumper stickers, are often used by individuals as a way of demonstrating support for political or ideological causes. Identification of vehicle registration and last service details are two examples of stickers on the inside of most car windscreens. The term "window sticker" is generally used for vinyl labels which are stuck to the inside of a vehicle's window, as opposed to water-resistant stickers that are stuck to the outside of a vehicle but can be affixed to anything.

Stickers are also used for embellishing scrapbooking pages. Kinds of stickers sold for this purpose include acrylic, 3D, cardstock, epoxy, fabric, flocked, sparkly, paper, puffy, and vellum. While in the earlier days of scrapbooking stickers were sold mostly on 2"x6" sheets, now 6"x12" and even 12"x12" size sheets are very common.

Stickers applied to guitars are called guitar decals. Post-it notes are removable stickers having glue on only part of the back, and are usually sold blank.