Many scanners support the attachment of document feeders which allow a large number of sheets of paper to be automatically scanned in succession. Various types of unsupervised batch scanning are also possible with a minimum of support needed in the back end (driver). Similarly, the 'net' back end passes requests and data between the local front end and the remote host. The saned daemon acts as a front end locally, but simply passes requests and data between the network connections and the local scanner. On client machines a 'net' back end (driver) connects to the remote host to fetch the scanner options, and perform previews and scans. On a host with a scanner, the saned daemon runs and handles network requests. One consequence of this separation is that network scanning is easily implemented with no special handling in either the front ends or back ends. Other options can be presented using GUI elements appropriate to their type e.g., sliders, drop-down lists, etc.

By convention there are several 'well known' options that front ends can supply using convenient GUI interaction e.g., the scan area options can be set by dragging a rectangular outline over a preview image. Each option has a name, and information about its type, units, and range or possible values (e.g., enumerated list). These options specify parameters such as the resolution of the scan, the scan area, colour model, etc. Whereas a TWAIN driver handles the user interface as well as communications with the scanner hardware, a SANE driver only provides an interface with the hardware and describes a number of 'options' which drive each scan.

SANE differs from TWAIN in that it is cleanly separated into ' front ends' (user programs) and ' back ends' (scanner drivers). Scanner Access Now Easy ( SANE) is an open-source application programming interface (API) that provides standardized access to any raster image scanner hardware ( flatbed scanner, handheld scanner, video- and still-cameras, frame grabbers, etc.). Public domain (SANE standard: API & network protocol) Weakened GPLv2 or later (backend libraries),

Easy scan software