  Quantum Algorithms have long captured the imagination of computer scientists
and physicists primarily because of the speed up achieved by them over their
classical counterparts using principles of quantum mechanics. Entanglement is
believed to be the primary phenomena behind this speed up. However their
precise role in quantum algorithms is yet unclear. In this article, we explore
the nature of entanglement in the Grover's search algorithm. This algorithm
enables searching of elements from an unstructured database quadratically
faster than the best known classical algorithm. Geometric measure of
entanglement has been used to quantify and analyse entanglement across
iterations of the algorithm. We reveal how the entanglement varies with
increase in the number of qubits and also with the number of marked or solution
states. Numerically, it is seen that the behaviour of the maximum value of
entanglement is monotonous with the number of qubits. Also, for a given value
of the number of qubits, a change in the marked states alters the amount of
entanglement. The amount of entanglement in the final state of the algorithm
has been shown to depend solely on the nature of the marked states. Explicit
analytical expressions are given showing the variation of entanglement with the
number of iterations and the global maximum value of entanglement attained
across all iterations of the algorithm.
