Usual knitting leaves a slightly bumpy horizontal edge. Of course this doesn't matter if this is the side of the back of a jumper and you are sewing it up, but if it's a blanket you're knitting then a straight edge looks sleeker.
It's so easy, as I learned from the two patterns: all you have to do when knitting garter stitch is slip the first stitch on each row over to the right hand needle then keep knitting as usual.
The first pattern I discovered this on was the Susan Crawford collar that I mentioned in a previous post. The curved edge looks very neat with the sl 1 technique. The collar took the length of seven episodes of Grey's Anatomy on DVD to knit over two nights. Here's me modelling it:
Here's a close up of the edge:
The other pattern I started that uses the sl 1 technique is a MillaMia baby blanket. The sisters who run MillaMia are Swedish but as they are based in London I'm including them under modern British knitting. The blanket is wonderfully colourful and the sl 1 technique gives it a sleek edge. Where I may have gone wrong though is the one stitch that 'bleeds' in to the next colour, however I did follow the pattern.
I'm currently crocheting a Toft Alpaca elephant whilst I take a break from the two jumpers I'm working on. How come the men in my life all wear size extra large? It would be much quicker if they were a size small instead!