Encryption can be used for any imaginable form of online communication. Users can use chat systems, speak to each other, transfer files or carry out bank transactions in encrypted form. Some of the most common usage cases for encrypted communication can be found here.

We have summarised information on data encryption (such as encrypting a USB stick) in a separate section.

E-mail communication

Millions of e-mails are sent all round the world via the internet every day. The senders and recipients use a huge variety of e-mail programmes to do so. In order to send messages, the e-mail providers that underpin this in turn use various online hubs to which the e-mails are sent and forwarded until they reach the recipient's e-mail program. Along these paths through the (generally unencrypted) internet, the e-mail can potentially be read by other people. We have summarised why this is so and how it can be avoided in the expert article E-mail Encryption.

Internet phones/VoIP, make encrypted phone calls

Internet phone conversations can be made in encrypted form using the Secure Real-time Transport Protocol (SRTP). This is an encrypted variation of the RTP protocol, which is responsible for transporting data in Voice over IP connections. Not all internet phone providers support SRTP, however. In order to enable an encrypted connection to be created, the end device of the conversation partners must be able to handle SRTP. It is therefore recommended that wherever necessary and possible, SRTP should be activated in both the configuration interfaces of the provider and in the end device or telephone software.

There also exist VoIP systems that are based on a similar encryption to browsers. It makes sense to combine this TLS encryption with SRTP in order to allow the SRTP keys to be exchanged in encrypted form.
In addition, there are internet telephone providers that have developed their own security and encryption mechanisms and offer these to their own customers only. More about Voice over IP.

Virtual Private Networks (VPN): Encrypted connections

Virtual private networks can be figuratively thought of as a tunnel through the internet. Participants in this type of network communicate with each other through this tunnel separately from all other data packets. VPN operators often use encryption in order to make the communication bug-proof and to protect it against manipulation. The end-points of a VPN can be computers, but also smartphones or routers. For example, a notebook user can log into a public WLAN and connect to their company's VPN. From that point on, they can exchange information with the company server in encrypted form.
Many home routers also now offer VPN functions. The owner of these types of devices can connect to their home network remotely via an encrypted channel.

Further information on VPNs can be found here.

Browsers: encrypted surfing

Most users have undoubtedly encountered encryption when surfing the internet, even if they mostly have no idea that this is the case. For example, when carrying out banking transactions, you often hear that you should make sure that the website address begins with https://. This just means that the connection is encrypted. The processes used here are called SSL and TLS. The encryption does not need to be activated separately, it takes place in the background.

You can find the important information about browser security here.