if you have a desktop computer without access to the Internet - then the private key. you save MEW and use it. to sign the transit offline as there are methods and instructions
Myetherwallet is secure. But don't share the private key. This important for your account safety. So your responsible for your account. Before use the wallet learn the wallet rules and regulation. Then easy and safely use. It good future saving and it net easy to hack. So it help to received the ethereum and token. It useful to future growth. So it good future safety wallet. So safely use it. Most of the people use the wallet for save the token.