Segmented control is a set of selectable buttons to make some choice. It can be considered as a replacement of radio buttons, that has higher emphasis to attract a user’s attention.
It is important that segmented control is almost never an alternative to tabs. While tabs are static and are used to access some specific user interface or data type (not dynamic categories), segmented control is used to make a selection of more domain specific entity. I.e. tabs are used to navigate the system, and segmented control is used to navigate or select domain-specific data or property.