1. The problem asks us to identify whether $x + 8 = x - 6$ is an expression or an equation. 2. An expression is a combination of numbers, variables, and operations without an equality sign. 3. An equation is a mathematical statement that shows two expressions are equal, indicated by an equality sign $=$. 4. The given statement $x + 8 = x - 6$ contains an equality sign $=$, which means it is an equation. 5. Therefore, the correct identification is Option A: Equation.