What is an Electron Application?
An electron application or electron app is an application made using Electron, a development tool used for turning webpages and web applications into standalone desktop applications and apps for smartphone, meaning that a web browser isn't necessary to use the web application.
More accurately, meaning that instead of you opening your web browser to access a webpage that works like an app, you install an entire web browser for opening only that single webpage but this web browser has no address bar so it doesn't look like you just installed an entire web browser just for this.