Foundation Double Crochet (FDC)
Great for creating a base with a little more S T R E T C H than your plain ol' chain.
Do you feel like your hat brims don't stretch over your head? Or are your blankets wider at the top than at the bottom??
The typical method for beginning a project is usually, "Chain x number of stitches..." and, often, this leads to a very unforgiving base in terms of stretch capability. These foundation type stitches are the perfect remedy for that. They can be done in most basic stitch styles - single, double, triple crochet. You are essentially crocheting your starting chain and first row at the same time.
This is the tutorial for Foundation Double Crochet (FDC):
YO and insert hook into 3rd Ch from hook. Draw up a loop. YO and pull through ONE LOOP. This creates your base chain. YO and pull through two loops, YO and pull through two loops. One FDC complete.
YO and insert your hook into the "V" created when you pulled through one loop only during the stitch before. Draw up a loop. YO and pull through ONE LOOP. Finish the DC as normal (YO pull through two, YO pull through two).
Continue for length of stitches needed.
You are, basically, crocheting upside-down with this stitch. To complete subsequent rows, you will work into the stitches opposite those "V's" you created with your FDC.