(called \texttt{blockIdx} \index{CUDA keywords!blockIdx} in CUDA) and of the
thread index (called \texttt{threadIdx}\index{CUDA keywords!threadIdx} in
CUDA). Blocks of threads and thread indexes can be decomposed into 1 dimension,
-2 dimensions, or 3 dimensions. {\bf A REGARDER} According to the dimension of manipulated data,
-the appropriate dimension can be useful. In our example, only one dimension is
+2 dimensions, or 3 dimensions. According to the dimension of manipulated data,
+the dimension of blocks of threads must be chosen carefully. In our example, only one dimension is
used. Then using the notation \texttt{.x}, we can access the first dimension
(\texttt{.y} and \texttt{.z}, respectively allow access to the second and
third dimension). The variable \texttt{blockDim}\index{CUDA keywords!blockDim}
