Add information to README

Author: sbabcoc

README.md

@@ -1,2 +1,34 @@
-# htmlunit-remote
-Remote wrapper for HtmlUnitDriver
+# INTRODUCTION
+**HtmlUnit Remote** is driver service for [HtmlUnitDriver](https://github.com/SeleniumHQ/htmlunit-driver) that enables you to acquire driver sessions from [Selenium 4 Grid](https://www.selenium.dev/documentation/grid).
+
+### Background
+
+**Selenium 3 Grid** could be configured to supply **HtmlUnitDriver** sessions, supported by special-case handling within the Node server itself. This handling was not carried over into **Selenium 4 Grid**, which was completely re-engineered with new architecture and vastly expanded capabilities.
+
+To eliminate behavioral differences between local and remote configurations, the [Selenium Foundation](https://github.com/sbabcoc/Selenium-Foundation) framework always acquires browser sessions from a **Grid** instance, managing a local grid instance when not configured to use an existing instance. The lack of **HtmlUnitDriver** support in **Selenium 4 Grid** necessitated reconfiguring the project unit tests from using this Java-only managed artifact to using a standard browser like Chrome, an external dependency that requires additional resources and imposes additional risks of failure.
+
+The driver service implemented by **HtmlUnit Remote** enables **Selenium 4 Grid** to supply **HtmlUnitDriver** session.
+
+### Implementation Details
+
+**HtmlUnit Remote** provides the following elements:
+* **HtmlUnitDriverInfo** - This class informs **Selenium 4 Grid** that **HtmlUnitDriver** is available and provides a method to create new driver instances.
+* **HtmlUnitDriverService** - This class manages a server that hosts instances of **HtmlUnitDriver**.
+* **HtmlUnitDriverServer** - This is the server class that hosts **HtmlUnitDriver** instances. It implements the [W3C WebDriver protocol](https://www.w3.org/TR/webdriver2):
+	* Create new driver sessions
+	* Route driver commands to specified driver sessions
+	* Assemble driver method results into HTTP responses
+
+In operation, **HtmlUnitDriverService** is instantiated by **Selenium 4 Grid** node servers that are configured to support **HtmlUnitDriver**. Unlike other driver services, which launch a new process for each created driver session, **HtmlUnitDriverService** starts a single in-process server that hosts all of the driver sessions it creates.
+
+### Grid Configuration
+
+```
+[node]
+detect-drivers = false
+[[node.driver-configuration]]
+display-name = "HtmlUnit"
+stereotype = "{\"browserName\": \"htmlunit\"}"
+```
+
+> Written with [StackEdit](https://stackedit.io/).