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+# Overview
+
+Sweep is an embedding of SWI-Prolog in Emacs.  It provides an
+interface for executing Prolog queries and consuming their results
+from Emacs Lisp.  Sweep further builds on top of this interface and on
+top of the standard Emacs facilities to provide advanced features for
+developing SWI-Prolog programs in Emacs.
+
+## Main Features
+
+Some of the main benefits that Sweep brings to working with Prolog
+code in Emacs are:
+
+- Semantic highlighting
+- Automatic indentation
+- Structural editing and navigation
+- Jumping to predicate definitions and references
+- On-the-fly diagnostics
+- Intelligent code completion
+- Refactoring support
+- Integrated SWI-Prolog top-level
+- Ability to run Prolog queries directly from Emacs Lisp
+
+These features and others, along with many options that Sweep provides
+for you to customize its behavior, are documented in [the Sweep manual](https://eshelyaron.com/sweep.html).
+
+# Installation
+
+Installing Sweep requires:
+
+-   Emacs 27 or later, and
+-   SWI-Prolog 8.5.18 or later.
+
+Sweep is available from NonGNU ELPA, to install it simply type in
+Emacs `M-x package-install RET sweeprolog RET`.
+
+Note that in Emacs prior to version 28, you need to explicitly enable
+NonGNU ELPA by adding something like the following to your Emacs
+configuration:
+
+    (with-eval-after-load 'package
+      (add-to-list 'package-archives '("nongnu" . "https://elpa.nongnu.org/nongnu/")))
+
+To upgrade Sweep to a newer version, do `M-x package-upgrade sweeprolog RET`.
+
+# Getting Started
+
+After installing the `sweeprolog` Elisp library, load it into Emacs:
+
+    (require 'sweeprolog)
+
+Sweep tries to find SWI-Prolog by looking for the `swipl` executable
+in the directories listed in the Emacs variable `exec-path`.  When
+Emacs is started from a shell, `exec-path` is initialized from the
+`PATH` environment variable which normally includes the location of
+`swipl` in common SWI-Prolog installations.  If the `swipl` executable
+cannot be found via `exec-path`, you can tell Sweep where to find it
+by setting the variable `sweeprolog-swipl-path` to point to it:
+
+    (setq sweeprolog-swipl-path "/path/to/swipl")
+
+All set!  You can now use Sweep for Prolog development and for integrating
+Prolog into your Emacs Lisp code.  For a full description of the different
+features of Sweep, see [the Sweep manual](https://eshelyaron.com/sweep.html).