Party Line, right and left struggle

[Kamil]

Lets get into this whole "party line" concept. What is the basic definition of the party line (I know what it is but I'd like to establish a specific frame of reference), and how do these "right" and "left" deviations and oppositions supposedly emerge? I'm refering to all the Ray of Light and Maoist stuff mainly. What basis does this have in the original works of Marx and Engels? I'm not questioning its validity, just seeking clarificaion on the meaning of terms from the perspective of the people who use them, and what is the textual evidence behind it? What historical examples are there of these trends occuring in the history of a Party?

[Jose Gracchus]

Its mostly Maoist lunacy and/or the internal politics of bureaucratically centralist sects, dominated by a personality-based leadership and cliques of support.