Here at Trend Patterns HQ we never need to use unpickers because we never make mistakes....

But if you find you have made a mistake with your sewing, having an unpicker is very useful. 

Unpickers are also known as seam-rippers, quick-unpicks.

You insert the unpicker between the stitches and pull up so the trends are cut by the small blade. Make sure your unpicker is sharp, otherwise it can cause damage to your garment by pulling the trends.