Usability refers to the usability of digital products - for example, apps, websites, software and online stores. It always focuses on the relevant target groups and users. Usability is a value that determines whether a product supports users in achieving their personal goals.
The international standard DIN ISO 9241-11 defines usability in the following way:
"Usability is the extent to which a system can be used by specific users in a specific context of use to achieve specific goals effectively, efficiently, and satisfactorily. " (DIN ISO 9241-11)