HTML: https://www.w3schools.com/html/default.asp
CSS: https://www.w3schools.com/css/default.asp
SASS: https://www.w3schools.com/sass/default.asp
Javascript: https://www.w3schools.com/js/default.asp
JSON: https://www.w3schools.com/js/js_json_intro.asp
Typescript: http://www.typescriptlang.org/
https://code.visualstudio.com/docs/typescript/typescript-tutorial
Angular 2+: https://angular.io/docs