There’s over 150 pages of information in this dynamical systems textbook written by Shlomo Sterberg, professor of Mathematics at Harvard University.
Free Differential and Difference Equations Textbooks
Differential equations is an advanced mathematics course generally introduced at the undergraduate level. One source defined them as “a mathematical equation for an unknown function of one or several variables that relates the values of the function itself and its derivatives of various orders…the are used specifically whenever a deterministic relation involving some continuously varying quantities (modeled by functions) and their rates of change in space and/or time (expressed as derivatives) is known or postulated.”
Difference equations are considered a type of recurrence relation which is an “equation that recursively defines a sequence, once one or more initial terms are given: each further term of the sequence is defined as a function of the preceding terms.”
Both types of equations have applications in engineering, physics, computer science, economics and other academic disciplines. Both types of equations are covered in the textbooks that I’ve listed here. If anyone is willing to supply me with better explanations of the two mathematical concepts, I would love to include it here rather than risk writing something that is incorrect.
For those students whom require an answer and need to learn how to work with these equations, the following list of free online differential equations textbooks and free online difference equations textbooks should hopefully help.