1. A method of creating a computerized model for computing values representative of traffic congestion in respect of a geographic area for use in representing a degree of traffic congestion in the geographic area using a limited number of symbols, the method comprising: retrieving, by at least one server from at least one database, historical traffic data in respect of roads within geographic area, the retrieved historical traffic data including data over a course of a first period of time in respect of second periods of time within the first period of time; retrieving, by the at least one server from the at least database, values representative of traffic congestion in respect of roads within the geographic area for the second periods of time; and deriving, via the at least one server, a computerized model for computing values representative of traffic congestion in respect of roads within the geographic area for third periods of time, the computerized model being based on the retrieved historical traffic data and the retrieved values representative of traffic congestion in respect of the geographic area for the second periods of time.