Preload is a pretty new term in the world of web development. We see this term in font usage and its meaning is simple: Preload web fonts to improve loading speed.

A simple example of preload could be:

<link rel="preload" href="/assets/Pacifico-Bold.woff2" as="font" type="font/woff2" crossorigin="">

Where to add

As preload means that we want something to be ready before something else is easy to understand that we want to write our HTML code right before the </head> tag in the header of our page.