If you ever do graphics design work in which you have manufactured items and containers in the scene, you may decide you need to create a barcode (UPC) on one of the items. But you don't want to cut and paste a real one, since this could get you into trouble with the company. So you need to create a fake one that looks like the real thing. Photoshop can help you do this.
Open Photoshop. Go to "File" and click "New." Make the size settings whatever you like. Then go to the Layer panel and click on the "New Layer" icon.
Go to the Toolbar, then the "Shapes" tool, and select "Line." Hold down the shift key and draw one short line.
Now go to "Filter" and select "Noise," and click "Add Noise." Make the "Amount" setting 110.
Go to "Edit," then "Transform," and click on "Scale." Then drag up the middle handle to raise the height to get the bars part of your barcode.
Go to the Toolbar, and under the bars, type in a series of random numbers to serve as your barcode numbers.