add: frost example and user manual reference

README.md

@@ -1,12 +1,34 @@
 # Frost
 
-**Frost** is a modern systems programming language that combines the speed of C
-with modern language features. It offers static typing and compiles to
+**Frost** is a modern systems programming language that combines the speed of
+`C` with modern language features. It offers static typing and compiles to
 [LLVM IR](https://llvm.org/docs/LangRef.html), delivering high performance while
 remaining accessible and easy to learn. Whether you're building system tools or
 performance-critical applications, Frost provides the low-level control you need
 with the convenience of contemporary programming practices.
 
+## Example
+
+Here's a simple "Hello, world!" program written in Frost:
+
+```frost
+import "https://frost-lang.deno.dev/std/io.ff"
+
+main: never -> int = {
+  printf("Hello, world!\n")
+
+  0
+}
+```
+
+To compile and run the program, save it to a file (e.g., `hello.ff`) and use the
+Frost compiler:
+
+```
+$ frostc -i hello.ff | lli
+Hello, world!
+```
+
 ## Features
 
 - **Static Typing**: Catch type errors at compile time, improving safety and
@@ -20,10 +42,11 @@ with the convenience of contemporary programming practices.
 
 ## Getting Started
 
-To get started with Frost, download the latest release from the
-[releases page](README.md) or build from source. You will need to have
-[Haskell](https://www.haskell.org/) and [LLVM 19](https://llvm.org/) or newer
-installed on your system.
+To begin with Frost, ensure that [Haskell](https://www.haskell.org/) and
+[LLVM 19](https://llvm.org/) or later are installed on your system. You can
+download the latest release from the [releases page](README.md) or opt to build
+Frost from source. For comprehensive installation guidance, please consult the
+[Documentation](https://frost-lang.gitbook.io/frost/user-manual/getting-started).
 
 ## Examples
 
@@ -34,3 +57,6 @@ structures, and how to interact with the system.
 ## License
 
 Frost is licensed under the MIT License. See [LICENSE](LICENSE) for details.
+
+```
+```