What does it mean to 'fasten off'?

I am making my first non-scarf/bag/dishcloth project and ran into a question. I am making Lion Brand Mittens of Jiffy Thick and Quick (free pattern) and for the top of the mitten it says 'with smaller needle, purl across (ok). Fasten off, leaving a 1 yard tail." Does this mean to bind off? The next lines have no numbers but say to thread the tail onto needle and slip thru al sts, pulling tightly to gather. Is that all i have to do to fasten off? Thanks in advance - i really want my mittens to work!

Yep that’s all you need to do. Thread your tail on a needle, the pull through all the stitches to close up the top.