QR codeA QR code (quick-response code) is a type of two-dimensional matrix barcode, invented in 1994, by Japanese company Denso Wave for labelling automobile parts. A barcode is a machine-readable optical image that contains information specific to the labelled item. In practice, QR codes contain data for a locator, an identifier, and a website visitor tracking. To efficiently store data, QR codes use four standardized modes of encoding (i) numeric, (ii) alphanumeric, (iii) byte or binary, and (iv) kanji.
Security engineeringSecurity engineering is the process of incorporating security controls into an information system so that the controls become an integral part of the system’s operational capabilities. It is similar to other systems engineering activities in that its primary motivation is to support the delivery of engineering solutions that satisfy pre-defined functional and user requirements, but it has the added dimension of preventing misuse and malicious behavior. Those constraints and restrictions are often asserted as a security policy.
Abstract family of languagesIn computer science, in particular in the field of formal language theory, an abstract family of languages is an abstract mathematical notion generalizing characteristics common to the regular languages, the context-free languages and the recursively enumerable languages, and other families of formal languages studied in the scientific literature. A formal language is a set L for which there exists a finite set of abstract symbols Σ such that , where * is the Kleene star operation.