The set of brackets {{}} when used with an HTML tag, represent data from a component. For example, on a HTML page which has <h1>{{variableName}}</h1>, here the ‘variableName’ is actually typescript (component) data representing its value on the template; i.e., HTML. This entire concept is called String Interpolation.
Angular 6 Components are the most simple Data building particuler block of a web UI in Angular 6 web applications and it some Data controls views (HTML/CSS).
ng g component login
D:\Angular\DemoApp>ng g component login
login.component.html
login.component.spec.ts
login.component.ts
login.component.css
app.module.ts