1. An object or group of objects that occupy a particular plane on a template. Each layer can include one or more text objects, images, barcodes, shapes and lines, and each template can include one or more layers, each of which can be shown or hidden, and which can be stacked on top of each other.
2. In the Aztec Code symbology, a data layer refers to a two-module-wide row of data and correction characters that wraps clockwise around the central finder pattern. Each data layer begins immediately beside the ending edge of the preceding layer and ends beside its own starting edge. As a result, a barcode scanner can read the data layers as a continuous spiral.