1. The problem is to simplify the expression $b^2$. 2. This expression represents the square of the variable $b$, which means $b$ multiplied by itself. 3. The formula for squaring a number or variable is: $$x^2 = x \times x$$ 4. Applying this to $b^2$, we get: $$b^2 = b \times b$$ 5. Since there are no further operations or values given, the expression $b^2$ is already in its simplest form. 6. Therefore, the final answer is: $$b^2$$