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 # Poisson Equation with overlap and Dirichlet 
 
 We solve a homogeneous Poisson (i.e. Laplace) equation with domain decomposition.
-The domain is a 2 by one rectangle, with boundary conditions $`u(0, y) = 0, u(2, y) = 2`$ and homogenuous von Neumann conditions on the other edges. The analytical solution is $`u(x,y) = x`$.
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+The domain is a 2 by one rectangle, with boundary conditions $`u(0, y) = 0, u(2, y) = 2`$ and homogeneous von Neumann conditions on the other edges. The analytical solution is $`u(x,y) = x`$.
+
+This tutorial illustrates overlapping DDM. The first domain solves the equation for $`x`$ ranging from 0 to 1.2, and the other domain from 0.8 to 2. They exchange data over the center of the domain (0.8 to 1.2), which provide the boundary conditions on the inner boundaries.
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