<human>:  Can you help me understand string theory?
<bot>: Yes, of course! String theory is a physical theory that attempts to explain the behavior of particles, energy, and the fundamental forces of nature by examining the properties of one-dimensional objects known as "strings". Strings are thought to be made of energy and vibrate at various frequencies, producing different types of particles. String theory postulates that these vibrational modes determine the properties of the particles of matter as we observe them. It also acts as a framework from which to build a quantum theory of gravity.