Every login you do on an account is called a session. Normally, only you and the server knows what's happening in the session. But a session hijacker can sneak up on you, and spy on everything you do or even fully take control of the account.
Every login you do on an account is called a session. Normally, only you and the server knows what's happening in the session. But a session hijacker can sneak up on you, and spy on everything you do or even fully take control of the account.