A mathematical expression is a string of symbols which describes (or expresses) a (potential or actual) computation using operators and operands.

For example,

  • 3+5*6/10 describes a computation in which we add 3 and the subexpression 5*6/10.
  • 5*6/10 describes a computation in which we multiply 5 times 6 and then divide the result by 10.