To simplify the expression \(\frac{b^{12}}{b^{4}}\), we can use the property of exponents that states:
\[ \frac{a^m}{a^n} = a^{m-n} \]
In this case, we have \(a = b\), \(m = 12\), and \(n = 4\).
So, we apply this property:
\[ \frac{b^{12}}{b^{4}} = b^{12 - 4} \]
Now, we subtract the exponents:
\[ b^{12 - 4} = b^{8} \]
Thus, the simplified expression is:
\[ b^{8} \]