Encrypting data means information is made unreadable and can only be read using a secret 'key' to unlock it (called decryption). If you're dealing with confidential information, you may need to encrypt it. Teesside's Information Security Policy offers guidance on this. If you're not sure, check with the IT department.
Remember, mobile devices and portable media, which includes laptops, external hard drives, USB memory sticks, CD/DVDs, etc. pose particular risks because they are easily lost, misplaced, or stolen. So, encryption can be used to protect the information. Data encryption can be applied to both stored data (on computer drives or USB storage devices) and data being transferred via networks.
You should make sure you only use encryption software approved by your institution. There is a guide to encryption on the IT Services self help page here.