Chaitin s algorithmic definition of random strings - based on the complexity induced by self-delimiting computers - is critically discussed. One shows that Chaitin s model satisfy many natural requirements related to randomness, so it can be considered as an adequate model for finite random objects. It is a better model than the original (Kolmogorov) proposal. Finally, some open problems will be discussed.
Keywords
Blank-endmarker complexity, Chaitin (self-delimiting) complexity, random strings.