Double Crochet / Treble Crochet

US terms: Double Crochet (dc)
UK terms: Treble Crochet (tr)

Usually marked by a T-shaped symbol with one crossbar on the stem.

How-to:

We yarn over the thread twice, insert the hook in the crochet piece and crochet the first stitch. We have three stitches on the hook. We crochet the first two stitches together. We have two stitches on the hook. We crochet them together and now have a double crochet stitch.

If this is our first stitch in a row, we must remember to insert the hook in the third stitch from the hook so as to gain the right height without misshaping the crochet piece. The remaining chain stitch is a turning stitch.