New to barcodes?

If you want to use barcodes "in-house" to ease tracking/inventory/selling etc. 

Then you can use any barcode type you like and invent your own identification codes; but remember, some barcode types support only numbers, other support uppercase letters and numbers, and a few support most of the keyboard! Most modern barcode scanners operate by connecting either in series with the keyboard or via USB - so scanning a barcode is much the same as typing the barcode data on the keyboard. You don't need special software to scan a barcode with a common scanner.

To make the barcodes you can use either a barcode creation program or component, or a label printing program or component as discussed below.

If you want to use barcodes for labelling product which will be sold in retail stores.

Then in most cases you cannot just invent the codes. You must register with your national article numbering body (GS1UK in the UK, the GS1US in the USA) to obtain a company code number and a range of product code numbers. Without these numbers your barcodes will not be recognised when you products are scanned at a retail outlet. Furthermore you will probably need to use either EAN (in Europe), JAN (in Japan) or UPC (in the USA) barcode types for retail products, and, if appropriate, you may need to use Code 128 or EAN 128 barcodes on boxes containing multiple items.
For contact points in most countries see our support site. If you need the barcode images see Where can I get a barcode?

For more information be sure to see Bar Coding - Getting it right (courtesy GS1 UK)

If you only have a small number of identical products

Then you may decide to create just one barcode for each product artwork and have a printer produce your boxes or labels. In this case all you need is a low-cost barcode image creator, so that the barcode image can be placed on your artwork.
Suggestion: See Where can I get a barcode? or Consider using Really Simple Barcodes - download a testware version and play with it for a few minutes.

If you need to generate a large number of barcode labels

Then a labelling printing database is probably most efficient. We normally recommend either a laser printer or, for very large quantities, a high-speed thermal printer. Ink-jet printer are not recommended because the ink can smudge, rendering the barcode un-scannable.
Suggestion: Consider using Really Simple Labels or dBarcode Suite - download a testware version, and play with it for half an hour. If you require 2D barcodes then AnyLabels is an excellent label printing system.

If you already have your data in an existing program

Then you need to decide whether it is possible/better to export the data into a label printing program, or add barcodes to your existing application. If you are using a modern database such as Access or Excel then a program such as AnyLabels, Really SImple Labels or dBarcode Suite could probably read your data directly - why not download a testware version and try it out?
Suggestion: Look at our recommendations for a wide range of applications.