Structural engineers use linear algebra a great deal, mainly because there are numerous equations with many unknowns associated with the analysis of a structure in equilibrium. Most of the time, these equations are linear, even when bending (material deformation) is involved. Linear algebra can also be used for other structural concerns, because it deals with the study of vectors, vector spaces, linear transformations, and systems of linear equations. Of course, linear algebra is not only used to understand structures; almost every subfield in engineering uses these types of mathematical calculations. (For more about linear algebra and linear equations, see “Algebra.”)