Very generally, Egyptian architecture is clean cut with straight lines and just about no cracks. Buildings and such were made to outlast time, and have so far. Of course you have the triangular pyramids and such, but most buildings, like temples and such, were very square, and statues were smoothed over very nicely.
There is a theory that pyramids were built according to the position of the sun and the moon, however it hasn't been proven, and I'm not sure myself.