1. A computer implemented method of analyzing speech utterances of a speaker in a given situation and context and determining behavioral, psychological and speech style characteristics of the speaker in the given situation, said computer implemented method comprising: creating a speech parameters reference database for classifying speech utterances according to various behavioral, psychological and speech styles characteristics, wherein the creating a speech parameters reference database for classifying speech utterances comprises: selecting manually a certain speaking context; selecting manually the behavioral, psychological and speech styles characteristics to be analyzed in the selected context; obtaining a plurality of speech utterances of people in the selected context; grouping manually the speech utterances into groups representing similar behavioral, psychological and speech styles characteristics; pre-processing each of the speech utterances in said groups of utterances representing similar behavioral, psychological and speech styles characteristics, into silent and active speech segments; dividing the active speech segments into strings of equal length blocks, wherein said blocks having primary speech parameters including pitch and amplitude parameters; deriving a plurality of secondary speech parameters from said primary parameters; and determining the unique secondary speech parameters, parameter combinations and parameters' values that are common to each group of utterances and represent the typical behavioral, psychological or speech styles characteristics of each group; obtaining speech utterances of a speaker in a specific situation and context; pre-processing the obtained utterances into silent and active speech segments and dividing the active speech segments into strings of equal length blocks, said blocks having primary speech parameters including pitch and amplitude parameters; and deriving a plurality of secondary speech parameters from said primary parameters; calculating speaker's unique speech parameters, parameters combinations and parameters' values representative of situational behavioral, psychological and speech styles characteristics, from said secondary parameters in the speech utterance; determining and scoring the situational behavioral, psychological and speech style characteristics in the speech utterance by comparing the calculated parameters with the pre-defined reference database of speech parameters; outputting the determined and scored results, wherein derived plurality of secondary speech parameters includes at least one of: average pause length, sum of pauses per time unit, average length of short silences, sum of short silences pertime unit, average length of equal pitch segments, sum of equal pitch segments pertime unit, average length of rising pitch segments, sum of rising pitch segments pertime unit, average length of falling pitch segments, sum of falling pitch segments pertime unit, average amplitude dispersion within equal pitch segments, average amplitude dispersion within rising pitch segments, average amplitude dispersion within falling pitch segments, pitch variance and range pertime unit, average pitch slope pertime unit, patterns of spectral shape and spectral envelope of the speech signal over time, patterns of sequential order of rising, falling and equal pitch trends over time.