Photoshop Elements >Pattern Stamp Tool
The tool is part of the tool family grouped with the Clone Stamp tool. The Pattern Stamp Tool paste something. What makes the two tools different is that they paste is the source of what is to be pasted.
The Pattern Stamp tool is in the tool family with the Clone Stamp tool.
The two tools paste something.
The difference is the source of the something-to-be-pasted.
The Pattern Stamp tool is pasting something on your image that came from a different image
You can find a tutorial here as to how to use the Pattern Stamp tool.
Here is a link to some patterns for Photoshop Elements or Photoshop