In iOS 12.2 and macOS 10.14.4, you may notice a new warning in the URL bar when browsing the web in Safari. It says the page you are visiting is “Not Secure”. But what does this mean? Are you less secure than you were before?
What does Not Secure mean in Safari?
iPhone and iPads running iOS 12.2 or later (or Macs with Safari 12.1 or later) will now say if the current Safari page is using secure HTTPS connection to the server, or not.
HTTPS means that all communication over the Internet for that page is encrypted and prevents any unscrupulous third-party from seeing or mutating the content of the page.