Question

I am having a hard time understanding what the major purpose of Google’s programming language Dart is. What’s its role? Why would I want to use it?

Answer 1

You may checkout the technical aspects on this article. Quote:

The Dart programming language is presented here in its early stages.
The following design goals will guide the continued evolution and
refinement of this open source project:

• Create a structured yet flexible programming language for the web.
• Make Dart feel familiar and natural to programmers and thus easy to
  learn.
• Ensure that all Dart language constructs allow high performance
  and fast application startup.
• Make Dart appropriate for the full range
  of devices on the web—including phones, tablets, laptops, and servers.
• Provide tools that make Dart run fast across all major modern
  browsers.

These design goals address the following problems currently
facing web developers:

• Small scripts often evolve into large web applications with no
  apparent structure—they’re hard to debug and difficult to maintain. In
  addition, these monolithic apps can’t be split up so that different
  teams can work on them independently. It’s difficult to be productive
  when a web application gets large.
• Scripting languages are popular
  because their lightweight nature makes it easy to write code quickly.
  Generally, the contracts with other parts of an application are
  conveyed in comments rather than in the language structure itself. As
  a result, it’s difficult for someone other than the author to read and
  maintain a particular piece of code.
• With existing languages, the
  developer is forced to make a choice between static and dynamic
  languages. Traditional static languages require heavyweight toolchains
  and a coding style that can feel inflexible and overly constrained.
• Developers have not been able to create homogeneous systems that
  encompass both client and server, except for a few cases such as
  Node.js and Google Web Toolkit (GWT).
• Different languages and formats
  entail context switches that are cumbersome and add complexity to the
  coding process.