Half double crochet
The half double crochet falls in between a single crochet and a double crochet in height.
Step by step
The half double crochet falls in between a single crochet and a double crochet in height.
To work a half double crochet,
yarn over and insert your hook into the stitch indicated in the pattern.
Yarn over and draw the yarn through the stitch.
You will have three loops on your hook.
Yarn over again and draw the yarn through all of the loops.
You have just worked a half double crochet.
Repeat the above steps until you have worked the number of stitches called for.
As you can see, crochet stitches are built from the top.
This is why you must work a certain number of chains at the beginning of each row to reach the height needed to work your stitches.
Half double crochet is two chains tall, so at the beginning of a row of half double crochet you have to chain two.
These chains count as the first half double crochet, so the following stitches should be worked starting with the second stitch from the previous row.