This is a computer-based technique to identify potential hits, or drug candidates, that bind to targets like protein receptors or enzymes. Using this approach, massive chemical libraries are quickly searched, hits are docked into protein targets, and then a scoring function is applied to determine the likelihood that a drug candidate would interact with the protein target with an affinity. The primary advantage of this screening process is that it considerably reduces the number of compounds whose activity is tested through experimentation, hence increasing the hit rate and improving the success rate of the in vitro tests. Designing a new drug usually takes around 10–15 years and costs over $2 billion before it is available in stores. Conventionally, drugs were mainly found in nature, but now we use automation and chemistry methods to discover them faster. Advanced technologies are being developed to make the early stages of drug discovery quicker and cheaper. For the purpose of early-stage drug discovery, this approach has been widely used by academic organizations and pharmaceutical corporations.