  The concept of fission barrier - a parameter which enters in quantitative
estimates of various observables related to nuclear fission - is presented from
the point of view of theory based on the picture of nuclear deformation and
energy dependent on it. We describe the macroscopic-microscopic method of
calculating energy landscapes which is simpler than the selfconsistent mean
field approach, and, due to its two-component nature, seems to be easier to
adjust to experimental data. We present some models and methods used to find
the fission saddles. For the purpose of illustration, we present results on
fission barriers in actinides and superheavy nuclei, obtained within one
macroscopic-microscopic model. We discuss comparisons with results of other
models, including some of the mean-field type.
