Gatsby 4.15 introduced a built-in `<Script>` component designed to improve website performance by offering various script loading strategies, helping developers manage scripts without negatively impacting user experience. The component allows for different loading strategies such as post-hydrate, idle, and off-main-thread, each with its unique benefits. The post-hydrate strategy loads scripts after the page is hydrated, providing immediate performance improvements over standard `<script>` tags. The idle strategy uses the browser's requestIdleCallback API, executing scripts when the main thread is free, while the experimental off-main-thread strategy utilizes Partytown to move resource-intensive scripts to a web worker, reducing the main thread's workload. A demonstration website was built to explore these strategies, revealing that while post-hydrate and idle offer similar performance, off-main-thread has specific use cases and trade-offs. Overall, the Gatsby `<Script>` component provides both power and flexibility for developers seeking to optimize script loading on their sites.