If you have a problem with quantum field theories of point particles, strings are one next possible option with the attractive features of being beautiful and rather robust mathematically. Historically string theory received attention as a model for hadrons, before QCD. Although work declined with the discovery of asymptotic freedom of QCD, suitable to describe quarks inside hadrons, people like Schwarz and Scherk realized that string theory could do much more than just describing hadrons, it provided a theory for quantum gravity. Today, string theory is the leading option to construct unified theories of all interactions.