The pen tool in photoshop is one of the neatest ways to isolate specific objects from photos, and pull them off their backgrounds to use with different background or to leave them on transparent backgrounds by saving the extracted object as a .png file with transparency.
|Simple Photoshop Tutorial for Pen-Tool (see below to download the complete tutorial)|
Sometimes the older methods still come handy for small touch ups, but if you can get the hang of this tool, it will become invaluable to you if you like saving "re-usable" bits and pieces of images on a transparent background. For designers, saving elements separately like this is essential.
Download the pdf HERE: Pen Tool Isolation in Photoshop