Step 1: Understanding orbital angular momentum.
The minimum orbital angular momentum of an electron in the hydrogen atom is given by the formula:
\[
L = n \hbar
\]
where \( n \) is the principal quantum number, and \( \hbar \) is the reduced Planck's constant, given by:
\[
\hbar = \frac{h}{2\pi}
\]
For the minimum orbital angular momentum, the electron is in the ground state where \( n = 1 \). Thus, the minimum angular momentum is:
\[
L = 1 \times \hbar = \hbar
\]
Step 2: Conclusion.
Therefore, the minimum orbital angular momentum is \( \hbar \).