SSL Port, also known as Secure Socket Layer port is by default related to HTTPS, re web server and work on port 443.
SSL is a protocol that one can use to transfer data using secure tunnel and not as plain text. It is not the SSL port that matters but what is the application that uses it. When we use the normal HTTP protocol to send and get data from the web everything that we send or receive is in plain text. This means that it is possible for anyone to read the data. This is exactly like reading this article. When we apply the SSL to the data on an alternative port, re SSL port 443, the data become encrypted and it is much harder for the hacker to read the data.
How SSL works:
When a web site is using SSL to encrypt its data the following is happens. The web site installs a certificate to the site. This certification includes a public key, a date that tells till when this certificate is valid. And the authority that generated this certification. There are some types of certificates and there is some organization that allows selling certificates.
From now on the protocol is a change to HTTPS. This is to notify you that this is a secure site. This means that all the data that transfer between the site to the user and from the user to the site is encrypted.
The user uses the public key from the site to encrypt the data before sending it to the site. On the site, there is a secret private key that known only by the site. With this key, and only with this key, the site is able to decrypt the data that was sent from the user and to use it.
There are also some other options to use the SSL certification. You can buy one yourself or use a shared one from your hosting providers. Starter sites may use the share one. But compies will want to use their own certification for extra trust form its users.
SSL is the most widely secure method that in use worldwide. Include credit cards, banking, other sites, and companies. There is an open SSL, free SSL integration open-source that site developers can use in their site creation. This way they can use the SSL port that they want to the application they create.