Double running stitch
Double running stitch is a linear stitch which is the same on the front and the back of the stitching if worked carefully.
Begin with a line of running stitch, bring your needle out from the back of the fabric and put it in a stitch length away. Then bring it back up the same distance from your first stitch as your first stitch was long. Work along the line repeating this, keeping your stitches and gaps the same length. When you reach the end of the line, work backwards along the line in exactly the same way with your new stitches filling in the gaps in the original line of stitching. So your new stitch will start at the end of one stitch from the last row, and finish at the end of the adjacent stitch. This creates one continuous line of stitching on both sides of the fabric. Remember to fasten your thread on and off to keep your stitching secure.