What does HTTPS upgrades mean?

Does Brave upgrade sites to https, or what does Https Upgrade mean?

@moses from https://support.brave.com/hc/en-us/articles/360022806212-How-do-I-use-Shields-while-browsing-

Connections Encrypted

This upgrades connections from HTTP to HTTPS based on HTTPS Everywhere’s rules. When enabled, Brave will use an encrypted connection on every site we know supports it. The number on the left shows how many individual connections were upgraded by these rules.

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