# Deno 1.x Highlights
These are the features that makes Deno so appealing.
## Native TypeScript support
TypeScript is deeply baked into Deno's runtime:
* You can write TypeScript by simply creating a `.ts` or `.tsx` file, without any additional configuration (tsconfig) or tooling
* Deno can execute TypeScript without a transpile step to convert it to JavaScript — Deno runs TypeScript, as-is
* This also powers [deno check](https://docs.deno.com/runtime/reference/cli/check/), type checking a program without execution
Being able to write .tsx or .ts without a .tsconfig or an additional transpile step is a huge quality of life improvement when it comes to writing TypeScript / code that scales with type safety.
## Complete JavaScript/TypeScript toolchain
Deno provides a complete and robust toolchain.
Unlike Node.js, where developers have to spend time evaluating and pulling together their own development toolchain, [all of that comes shipped and pre-configured with the Deno binary](https://docs.deno.com/runtime/reference/cli/benchmarker/).
This includes:
* deno test
* deno lint
* deno fmt
* deno check
* deno bench
* deno compile
and much more.
[Here's a cheatsheat of how to write common Node commands in Deno](https://docs.deno.com/runtime/reference/node/#node-to-deno-cheatsheet):
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## Web Platform APIs
Deno aims to narrow the gap between browser and server-side javascript, this means that it supports web APIs as exactly as possible, forces users to use ES Modules instead of CommonJS, and generally aims to have a "generic" feeling.
Deno supports [web platform APIs out-of-the-box](https://docs.deno.com/runtime/reference/web_platform_apis/), which means no longer needing to import a library like `superagent` and instead directly calling `fetch`. If you've ever built for the browser, you're likely already familiar with Deno. Conversely, if you're learning Deno, you're investing in your knowledge of the web.
Commonly used Web APIs in Deno:
* `Request` and `Response` objects
* `Fetch`
* `Prompt`
* `URL`
* `ReadableStream` / `WriteableStream`
[All web platform APIs supported in Deno.](https://docs.deno.com/api/deno/)
## Secure by default - prevent supply chain attacks
A program run with Deno has **no file, network, or environment** access unless explicitly enabled to alleviate concerns about npm modules introducing unexpected vulnerabilities.