Glossary of Label Technology

Automatic Application

A stipulation made by our customers whereby the finished labels will be applied by machine, so it is important that the labels are positioned uniformly on the reel and can be easily extracted.

Bar Code Check Digit

A check digit is a verifying character at the end of a bar code which is derived by means of a calculation of the other digits, e.g. "12348". The "8" is the result of a mathematical algorithm of the digits "1234". With some barcode types, the check digit is optional.

Bar Code Quiet Zones

The spacing on either side of the bar code. This can affect the read rate of the bar code, and consequently there are guidelines laid down according to each symbology type.

Bar Code Ratio

For bar code symbologies where there are only two thickness of bar this is the ratio between the width of the narrow and wide bars. For example, in a barcode where the narrow bar measures 1mm thick and the wide bars 3mm, then the ratio is therefore 3:1. Wide:narrow bar ratio should be consistent throughout the bar code.

Bar Code Symbology

Bar codes come in different formats or 'symbologies' and each has its own characteristics.

Bar Code X-dimension

The width of the narrowest bar of the bar code.

Butt Cut / Butted Together

When labels are positioned directly next to each other without gaps in between.


The cardboard tube that labels are wound onto. Available in different diameters to suit various printer models.

Direct Thermal

When using a thermal printer, information is printed directly onto heat-sensitive label material without the use of a ribbon.

Fan Fold

When pages of labels are folded concertina style to allow feeding into a dot matrix printer.


The spacing between labels.


On sheeted labels this is the spacing around the perimeter of the page.

N.E.L. or Narrow Edge Leading

Narrow Edge Leading or NELThis refers to the orientation of the labels on the roll. The labels are positioned with their narrower edges perpendicular to the sides of the roll.


Labels which can be removed without tearing or leaving any residue.


Radius corners.


See peelable.

Side Wastage

On rolls of die cut labels this is the gap running down either side of the label.

Sprocket Holes

Holes punched by the sides of the labels to enable use with dot-matrix or other tractor-fed machines.

Thermal Transfer

When using a thermal printer, ink is transferred through a ribbon by means of heat emitted from the print head.

Web Width

The width of the backing paper.

W.E.L. or Wide Edge Leading

Wide Edge Leading or WELThis refers to the orientation of the labels on the roll. The labels are positioned with their wider edges perpendicular to the sides of the roll.