The moment of inertia tensor differs from the moment of inertia in that it accounts for the distribution of mass in three-dimensional space, providing a more comprehensive understanding of an object's rotational dynamics. While the moment of inertia is a scalar value for symmetrical objects, the moment of inertia tensor is a matrix that reflects varying moments of inertia across different axes (x, y, and z) for non-symmetrical objects. This tensor can take vectors and one-forms as inputs, making it a more complex mathematical function. Understanding the moment of inertia tensor is crucial for analyzing rotational motion in physics and engineering. The discussion emphasizes the importance of this tensor in accurately describing the inertia of irregularly shaped objects.