Photoshop: Remove Background
To remove the background from an image, first find the Magic Want Selection tool.
Next, click the "Add to selection" button on the top toolbar. (See image below) Make sure you are on the layer that has the image you want to remove the background from. In the example, I am removing the background from the picture of the bird. You can see it selected in the layers panel on the right. Start clicking the background of the image--your selection will be surrounded by blinking dashed lines ("marching ants").
Once you are happy with your selection, hit the BACKSPACE key on your keyboard and the background should disappear. On your keyboard, press CTRL-D to deselect. The marching ants should disappear. You're done!
Note about selections: when you have an active selection, you can only edit what is inside the selection. If you're trying to paint or type or draw and it does't seem to be working, try hitting CTRL-D on the keyboard.