What is SSL/TLS?
SSL/TLS is the encryption protocol that secures the connection between a visitor's browser and the server hosting the site, symbolised by the padlock and the HTTPS prefix in the address bar.
Why it's essential for an online store
Without encryption, data exchanged between the visitor and the site (login credentials, address, information sent through the checkout) can be intercepted in plain text. SSL/TLS encrypts these exchanges. Its absence also has consequences beyond pure security: browsers show a “not secure” warning on HTTP sites, which hurts trust and conversion, and search engines use HTTPS as a ranking signal.
In practice
An SSL/TLS certificate is now most often obtained for free via Let's Encrypt, generally provided and automatically renewed by the host. A common issue once the certificate is set up is “mixed content”: some resources on the page (images, scripts) continue to be loaded over HTTP, which stops the padlock from displaying correctly despite a valid certificate.
Frequently asked questions
Are SSL and TLS the same thing?
Does an SSL/TLS certificate cost money?
Why doesn't the padlock appear even though the certificate is properly installed?
Describe your need in one minute
A few targeted questions so I can reply with an estimate rather than another questionnaire.