There are three major releases of Angular. The first version that was released is Angular1, which is also called AngularJS. Angular1 was followed by Angular2, which came in with a lot of changes when compared to Angular1.
The structure of Angular is based on the components/services architecture. AngularJS was based on the model view controller. Angular 4 released in March 2017 proves to be a major breakthrough and is the latest release from the Angular team after Angular2.
Angular 4 is almost the same as Angular 2. It has a backward compatibility with Angular 2. Projects developed in Angular 2 will work without any issues with Angular 4.
Let us now see the new features and the changes made in Angular 4.
The Angular team faced some versioning issues internally with their modules and due to the conflict they had to move on and release the next version of Angular – the Angular4.