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Encryption 101

Would you ever intentionally leave your wallet sitting out on a table at a restaurant or airport? Probably not. The risk of it getting in the wrong hands would be very high.

Now, think of the times you’ve shopped or filled out a job application online — without encryption, the information you enter would be as easy to grab as it would had you set your wallet out in public with a “take me” sign. 

So, what exactly is encryption? 

Simply put, encryption is a method of securing data by converting plain text (i.e., your credit card number) into a bunch of nonsense characters, rendering it useless to unauthorized parties. 

Encryption works by using algorithms that contain designated strings of characters called ‘keys’. A key is required both to encrypt the data (turn it into a bunch of nonsense), or decrypt the data (revert it to plain text). It’s similar to locking and unlocking a door. If you have the key to the door, you can lock and unlock it. Without the key you can stare at the door, but you're not going to get to the stuff inside.

Sometimes the same key is used to encrypt and decrypt the data, and sometimes there are different keys used to encrypt and decrypt the data — if you're curious to learn more about the different types of encryption, this article is a good place to start.

Why is encryption important? 

Encryption helps to keep sensitive information that is sent over the web from being stolen and used by nefarious actors. But just as important is knowing how to confirm that the apps and websites you use encrypt user data, and how to spot sites that may not. Here are a few tips: 

  • Use websites with "https." The sites use the current standard security protocol called transport layer security (TLS), which both encrypts data and authenticates the parties exchanging data. Some, mostly older, sites still have only "http" and are considered not secure — your browser may alert you of this. 

  • Make sure the wireless networks you join use WPA (Wi-Fi protected access) at the least. The newest version, WPA3, provides the most robust protection. This article does a good job of explaining the different levels of wireless security and how to check the security of your network. If a network is still using the old WEP (wired equivalent protection), don't use it. 

How to make sure your data is encrypted when you want it to be

When you’re sending and receiving data — buying socks on Amazon, for example — encryption is fairly straightforward, as long as both parties are using a secured network and up-to-date protocols such as "https". You should still follow basic security tips and be careful to only do business with reputable companies.

But what about files that are just sitting on your desktop or phone that you want to protect? Encrypting files at rest takes a little more work, but it's doable. Both Adobe Acrobat and the desktop versions of Microsoft Office apps offer built-in options to encrypt documents by applying a password. You can also purchase encryption tools from various vendors. 

The darker side of encryption

We'd be remiss not to mention that encryption can be used maliciously sometimes. Ransomware attackers utilize encryption to lock up their victim's files, and then demand a ransom to provide the key to decrypt the files. The 4Help Knowledge Base offers information on how to protect yourself from ransomware.

By and large, however, encryption is a vital part of cybersecurity, and knowing the basics about how encryption works and where, when, and why it's necessary can help you avoid potential threats and stay safer online.