Magnonics is an exciting research field that holds the promise of a new generation of energy efficient devices with significant impact on information technology. The fundamental concept of magnonics is to use the counter part of magnon, known as spinwaves, to carry and process information in the microwave regime. The wavelengths of spinwaves are orders of magnitude shorter than light waves operating at the same frequency range (i.e., at 20 GHz microwave has 3 cm in air, while the spin wave wavelength can be shorter than 100 nm), which makes them a suitable candidate for nanoscale on chip microwave signal processing and nanomagnonic devices. The building block for magnonics is the magnonic crystal which is an ordered arrays of nanomagnets with strong magnetostatic interactions. The magnonic crystals also formed magnonic minibands with allowed magnonic states separated by forbidden band gaps like electronic band structure in semoconductors. One of the key aspects of magnonics is to tune these bandgaps by varying various physical and geometrical parameters not only to answer fundamental questions concerning magnonics but also to provide a new generation of devices such as magnonic devices, spin wave logic devices, and spin wave multiplexers. The aim of our research is to tune the spin waves in magnonic crystals by changing its various physical and geometrical parameters such as material, shape, size, lattice spacing, lattice symmetry, and also strength and orientation of the external bias field.