This could have a different title, but I call it "chain sewing." It's a really fast way to put together multiple quilt blocks that are the same. Plus it saves you a ton of thread.
Take a look!
Here is what I would like to sew together (the beginnings of a star block).
Start with one side, place right sides together, and start sewing. Place your needle in the "down" position if you can on your sewing machine.
Sew down until you have about 1/4" left and get your second piece ready. Place that piece a couple of centimeters away from the first one and sew right onto it. It's okay if you sew a stitch or two and there's no fabric under the sewing needle.
When you've sewn all of your pieces, you'll have a chain like this one:
Don't snip your pieces apart just yet! Do the other side (if this applies).
NOW go through and snip your threads that are between the sewn pieces.
That's it! This process will save you tons of time if you've got a big project to do!