In this guide, we talked early on about how to avoid a character set in the meta tag. Character sets, or sometimes abbreviated as charset, are the set of characters, in this case numbers, that computers use to represent characters used for various languages. Without this, we would have a bunch of numbers and characters that the browser would not know how to translate properly.
Specify a Character Set Early
What is a Character Set?
Why Specify a Character Set Early?
How to Specify the Character Set
Specifying the character set can be done through the server or through the browser, however, the recommended method is to set it through the server as it avoids having to set it in in each HTML file. Basically, set it and forget it. However, if for some reason you cannot access your server, it can be set in the HTML file. This is better than not setting it at all, but just know that you may still get the optimization message to set the character set early if using this method.
Lighthouse is an open-source tool that is used to run an audit against your web pages and provides scores and suggestions for improving page performance, accessibility, SEO, and more.
PageSpeed Insights is a tool created by Google that reports on the performance of a page on both mobile and desktop devices, and provides suggestions on how that page may be improved.