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What is the Colle System?

From Wiki:
Ignoring Black's responses in order to consider White's moves only, the typical plan (in the Colle) is as follows:
1.d4 2.Nf3 3.e3 4.Bd3 5.0-0 6.Re1 7.c3 8.Nbd2 9.e4,
with White rearranging the move order appropriately. It is a perfectly solid scheme of development, but, inflexibly applied, it cannot offer more than equality against a vigorous Black response. It may be a good tool for avoiding book variations, for Blitz play, or for forcing opponents to think for themselves early on. These days it is considered totally innocuous, and is rarely seen at Master level or above.
The strategic plan behind the Colle System is to aim for a kingside attack. The black king's knight will be either exchanged off on e4, or driven away by the advance e4–e5. This removes a guard from the h7 square, often enabling a classic bishop sacrifice on h7 as the start of a mating attack. Some authors even call this sacrifice "Colle's sacrifice".
What is the Colle System?