Data is transferred between the OTB server and a user's browser using either the protocol https:// or http://

It is likely that you will have encountered both protocols while using the internet.

The main difference between https:// and http:// is the security of data in transit between the OTB server and client computers. "https" instructs the browser to initiate an encrypted session with the web server before sending any data.

If the web address begins with https://, that means your computer is talking to the website in a secure manner. https ensures that all subsequent interactions are encrypted. Others can not eavesdrop on this encrypted traffic.

https only protects data in transit from eavesdropping. Once data arrives at the destination, it is only as safe as the computer it is on; hence, the importance of not leaving the computer, logged in, and unattended.

If the web address begins with http://, the connection between the OTB server and your browser uses http, which sends all traffic as plain text; this is probably not appropriate for sensitive information. It is possible for someone to "eavesdrop" on your computer's conversation with the website.

However, a school network is likely to be more secure than the internet.  If your OTB server is connected directly to your network, you may decide that the encryption used by https is not necessary.