Photonics emerged in the 1960s and 1970s from work on semiconductor light emitters, lasers and optical fibres. Nanoscale effects impact on photonics, e.g. in the surface quality of waveguides and optical fibres. The focus here remains as closely as possible on photonics as it relates to nanotechnology, e.g. where nanotechnology enhances photonics and vice versa. Photonics more widely is also described and referenced.