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+# OpenKneeboard Calculator
+
+This is a basic calculator for [OpenKneeboard](https://openkneeboard.com); it also serves as a sample OpenKneeboard plugin.
+
+OpenKneeboard v1.9.9 or above is **required**; as of 2024-09-19, the latest release is v1.9.8, which is not capable of running this plugin.
+
+## Installation
+
+1. Install a new enough version of OpenKneeboard; as of 2024-09-19, this requires a development build of OpenKneeboard
+2. Download `Calculator.OpenKneeboardPlugin` from [the latest release](https://github.com/OpenKneeboard/calculator/releases/latest)
+3. Double-click it to launch the plugin installer in OpenKneeboard
+
+## Usage
+
+The buttons can be interacted with via a graphics tablet; OpenKneeboard has no keyboard input support; you can also tap on any number in the history to recall that value (like an 'MR' button, but more powerful).
+
+This plugin works like an "Endless Notebook" tab: the first time you use the calculator, a new, blank page with a blank calculator and history will be added. This lets you switch between several different sets of calculations easily.
+
+![screenshot](screenshot.png)
+
+## License
+
+This project is [MIT licensed](LICENSE).
+
+## Contributing
+
+While contributions are welcome, please keep in mind that this is meant to be:
+
+- a basic calculator
+- a simple sample plugin for OpenKneeboard developers
+
+This leads to some rules for this project that probably aren't the right choice for larger projects:
+
+- advanced features will not be added
+- no build systems or transpilers will be used, e.g. TypeScript, WebPack etc
+- no external dependencies; no npm
+
+Please contribute via GitHub issues/pull requests, or via `#code-talk` [on Discord](https://go.openkneeboard.com/discord).