1. A computer-implemented method for constructing and manipulating a Graphic User Interface (GUI), comprising: a) retrieving from a data repository first GUI data representing at least (i) an entity, (ii) attributes of an entity, (iii) a manipulatable scale associated with a respective attribute and signifying a level of significance of the attribute; b) constructing on a screen said GUI including converting said first GUI data into displayable GUI data which include at least said entity, its attributes and for at least one of said attributes a manipulatable scale and displaying said displayable GUI data; c) enabling a user to perform on said GUI a manipulation of at least one manipulatable scale of a respective attribute giving rise to manipulated displayable GUI data; d) converting said manipulated displayable GUI data into second GUI data representing at least one data record that includes attribute data corresponding to said attributes and scale data corresponding to scales associated with respective said attributes; and e) using said at least one data record or portion thereof for operations in said data repository.