SSL and the padlock
The padlock next to your address. Without it the browser warns visitors your site is not secure, and it costs nothing to have today.
SSL encrypts what travels between visitor and site. On an informational page it protects little, but its absence does real damage: Chrome puts 'Not secure' right next to your name.
Years ago it was a paid extra. Today it is free and automatic on any decent host, so a site without it signals something old or abandoned underneath.
It also counts in Google, though not much. What counts is the red warning your customer sees before deciding whether to call.
What to do about it
Type your address into a browser and look for the padlock. If you get a warning, call whoever handles your site today.
Other words about the same thing