For this reflection is based on structural walk we saw some examples of the building system in NYC by walking the high line. we visualize some of the material that all the building was made such as steel, brick, concrete and wood. So, by seeing all this type of those materials we can defined how forces can react of tension and compression. I think that most of the important thing about construct a building is the material was built. and also we can saw a lot building undersconstruction and realize how the built type is changing and how this work to built all nice building. Even though, we also saw the Whitney museum and their columns and also we saw in the bottom of the high line how the beam and girders works.