AMPL (A Mathematical Programming Language) is a modeling language for optimization problems. For these problems, AMPL allows users to create variables that will be optimized. Users then specify under which constraints these variables should be optimized. Once that's defined, AMPL converts the optimization problem into solver-specific formulations. In other words, you define the problem once in AMPL and you can then solve it with most available solvers without additional work.
https://en.wikipedia.org/wiki/AMPL
AMPL (A Mathematical Programming Language) is a modeling language for optimization problems. For these problems, AMPL allows users to create variables that will be optimized. Users then specify under which constraints these variables should be optimized. Once that's defined, AMPL converts the optimization problem into solver-specific formulations. In other words, you define the problem once in AMPL and you can then solve it with most available solvers without additional work.