Current state of art contains several methods to achieve intelligent tracking. Some methods are machine learning oriented. In these methods, activities are learnt from the context in an unsupervised or semi supervised manner. One other method is description based event recognition. In the heart of the method , describing scenarios wrt activities employed. For the description, a language is necessarily needed. There are mathematical languages in which logic is used to represent activities and their relations.Also some graphical languages such as hidden markov models, state machines, state charts are being used. Some textual languages proposed as well.