Ordinary Differential Equations

A differential equation is an equation that contains a function and it's derivatives. 

First Order Differential Equation
Second Order Differential Equations
Higher Order Differential Equations

External References

Edwards, C. H., & Penney, D. E. (2008). Differential equations and boundary value problems: computing and modeling (4th ed.). Upper Saddle River, NJ: Pearson Prentice Hall.