Module description: The cytoskeleon is an elaborate array of protein fibers that contributes to the maintenance of cellular shape and provides for other cellular functions, including cellular movement, cell division, endocytosis, and movement of organelles. The proteins self-assemble into filamentous structures of three types: actin filaments (microfilaments), intermediate filaments, and miccrotubules. Actin is the major component of the cytoskeleton. Actin filaments interact with actin crosslinkers to form different types of networks. One such network structure is a gel, where the filaments are equally distributed and show little or no preference in their orientation. Alternatively, filaments may also form the bundles, which bunch together in parallel arrays. These structures not only influence the shape of the cell and the cell's mechanical behaviour, but also provides a basic machinery for cell migration which requires an integration of localized, transient signalling events with changes in cellular architecture.