Don't understand the key tool stuff....

So I don’t understand the whole key tool, key store and alias stuff. Can someone explain what all that is so I can understand it better. It would help me alot. Thanks.

Keytool is a java tool to sign your application.
Read this: Sign your app  |  Android Studio  |  Android Developers
Than watch this: Using keytool to make a release key for android. - YouTube

The keytool allows you to sign the application so you can upload it to Google Play. Basically it’s security.

Ah ok. Thanks.

So I followed the video and my key kept getting denied. I don’t know why.