  In this work we perform a detailed numerical analysis of (1+1) dimensional
lattice $\phi^4$ theory. We explore the phase diagram of the theory with two
different parameterizations. We find that symmetry breaking occurs only with a
negative mass-squared term in the Hamiltonian. The renormalized mass $m_R$ and
the field renormalization constant $Z$ are calculated from both coordinate
space and momentum space propagators in the broken symmetry phase. The critical
coupling for the phase transition and the critical exponents associated with
$m_R$, $Z$ and the order parameter are extracted using a finite size scaling
analysis of the data for several volumes. The scaling behavior of $Z$ has the
interesting consequence that $<\phi_R>$ does not scale in 1+1 dimensions. We
also calculate the renormalized coupling constant $ \lambda_R$ in the broken
symmetry phase. The ratio $ \lambda_R/m_R^2 $ does not scale and appears to
reach a value independent of the bare parameters in the critical region in the
infinite volume limit.
