Update README.md

README.md

@@ -6,3 +6,33 @@ vector spaces and matrices. It borrows concepts heavily from Python's [NumPy](ht
 as well as Rust's [nalgebra](https://www.nalgebra.org/).
 
 The name is pronounced like "num-idge".
+
+## Features
+
+- A type-safe and efficient array type, based on NumPy's arrays.
+
+- Compile-time checked indexing operations to avoid run-time overhead.
+
+- Utility functions and operations for working with vectors, matrices,
+  homogeneous coordinates, and other linear algebra computations.
+
+- Transform types for working with rotations, reflections, isometries, and other
+  types of affine maps.
+
+## Planned Features
+
+- An IO-based mutable array type, useful for writing more efficient code.
+
+## Documentation
+
+Most of the exported utility functions have docstrings. There are also plans for
+an in-depth tutorial on NumIdr's features, though that is not available yet.
+
+## Usage
+
+Basic package install:
+
+``` shell
+idris2 --install numidr.ipkg
+```
+