We study the well-posedness of nonautonomous nonlinear delay equations in R
n
as evolutionary equations in a proper Hilbert space. We present a
construction of solving operators (nonautonomous case) or nonlinear semigroups
(autonomous case) for a large class of such equations. The main idea can be
easily extended for certain PDEs with delay. Our approach has lesser limitations
and much more elementary than some previously known constructions of such
semigroups and solving operators based on the theory of accretive operators. In
the autonomous case we also study dierentiability properties of these semigroups
in order to apply various dimension estimates using the Hilbert space geometry.
However, obtaining eective dimension estimates for delay equations is a nontrivial problem and we explain it by means of a scalar delay equation. We also discuss
our adjacent results concerned with inertial manifolds and their construction for
delay equations.