  The stringy picture behind the integrable spin chains governing the evolution
equations in Yang-Mills theory is discussed. It is shown that one-loop
dilatation operator in N=4 theory can be expressed in terms of two-point
functions on 2d worldsheet. Using the relation between Neumann integrable
system and the spin chains it is argued that the transition to the finite gauge
theory coupling implies the discretization of the worldsheet. We conjecture
that string bit model for the discretized worldsheet corresponds to the
representation of the integrable spin chains in terms of the separated
variables.
