In machine knitting, gauge can refer to one of several related concepts dealing with the spacing of needles carrying loops. The gauge of a machine is the count of needles per inch along its needle beds. The gauge of a fabric is the count stitches per inch, and may be different along courses and wales. Fabric gauge and machine gauge are related but not necessarily equal, since fabric can contract or expand after being knit.
Gauge can also refer to which needles are used to hold loops when creating a fabric. In full gauge knitting, all needles on a bed are used to hold loops. In half gauge knitting, single-needle gaps are left between needles that hold loops. In addition to producing a looser fabric, the empty needles in half gauge can be used as temporary locations for transfers or splits (especially useful on machines without sliders) or as knitting locations to, e.g., allow ribbing on a tube. In two-thirds gauge knitting, two-needle gaps are left between needles that hold loops; this allows knitting of four independent sheets of fabric (or two independent tubes). Changing gauge in the middle of knitting is possible, and sometimes desirable when using textures with different stretch behaviors.