I was blogging about tension and wound up involved in how the stitch happens and decided with all the pictures I took that it deserved it's own blog. So here it is
So, you have the top thread and then you have the bottom thread, and in the stitching process the 2 threads become looped around each other and make a stitch. The whole process is quite interesting. The needle goes into the fabric and down past the needle plate and when it gets down there the "hook" on the bobbin assembly catches the upper thead and takes it around the bobbin and it becomes looped around the bottom thread on it's way around and back up and a STITCH is born! That happens every time your needle goes down and for every stitch in your project. Now you know why it's so important to take care of your machine! It works hard for you.
So I've been sewing for over 30 years ( I learned to sew when I was 6 months old!) and didn't know how my machine worked until about 6 years ago. I think it's pretty cool!