When you knit socks from the toe up, it's really important to use a stretchy bind off, like the lace bind off, so the cuff of your sock doesn't dig into leg. Ouch! Nobody wants to wear a sock that cuts into their leg all day.
The lace bind off is different than a traditional bind. You never pass any stitches over each other. Instead, you work two stitches together along the edge. It's great for toe up socks, but you could also use it for any edge that you want to be a little more elastic like a shawl, sleeve cuffs of the neck of a sweater.
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