If you imagine that barcodes are used only on products that are sold in shops and supermarkets, you would be rather off the mark. These labels are used for many purposes as they are small but can carry lots of information not just a price of the item, can be easily scanned in restricted spaces in necessary.
Pricing of products is the most obvious and they also know the price of the product and avoid intentional or un-intentional mistake at the cash point.
ID cards are another popular use of the bar code label; most ID cards today will have barcodes on them, which are scanned using a swipe system. These are used to record the clocking on and clocking off times of employees and are also used in maintaining security at offices, by knowing the details of the persons entering in to the organisation.
Government departments and large organisation will often attach a self adhesive label which has a barcode printed onto it on items that are to be returned to the department. On scanning them, information such as, date, time and place of receiving, the person who has received it, person who prepared the documents is easily retrieved.
Events tickets for shows or pop concerts increasingly have a code on them which is scanned before entering the vent to see if it is genuine or a fake; they also register how many people are in the building.
Barcode labels are being widely used in hospitals to keep all the information related to patients documented. Attached to the wrist of the patient it can hold information about the patient such as date of birth blood type special diet and so on.
Mill order companies and increasingly parcel delivery companies and couriers use a self adhesive label to an item to relay information about delivery times and proof of delivery. Barcodes are helpful in tracking the information regarding the mails, where it is being circulated, etc.