What is a authenticator app?
An authenticator app is a mobile application that provides an second layer of security to your account by generating time-based, single use, 'Verification Code'. These 'Verification Codes' keep you safe by 'double checking' it is you logging in and not someone else using your password.
Where can I get one?
Speak to your IT Department about which they recommend you use as a company. Here are some examples: