  A great number of works is devoted to qualitative investigation of
Hamiltonian systems. One of tools of such investigation is the method of
skew-symmetric differential forms. In present work, under investigation
Hamiltonian systems in addition to skew-symmetric exterior differential forms,
skew-symmetric differential forms, which differ in their properties from
exterior forms, are used. These are skew-symmetric differential forms defined
on manifolds that are nondifferentiable ones. Such manifolds result, for
example, under describing physical processes by differential equations. This
approach to investigation of Hamiltonian systems enables one to understand a
connection between Hamiltonian systems and partial differential equations,
which describe physical processes, and to see peculiarities of Hamiltonian
systems and relevant phase spaces connected with this fact.
