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+# Abseil - C++ Common Libraries
+
+The repository contains the Abseil C++ library code. Abseil is an open-source
+collection of C++ code (compliant to C++11) designed to augment the C++
+standard library.
+
+## Table of Contents
+
+- [About Abseil](#about)
+- [Quickstart](#quickstart)
+- [Building Abseil](#build)
+- [Codemap](#codemap)
+- [License](#license)
+- [Links](#links)
+
+<a name="about"></a>
+## About Abseil
+
+Abseil is an open-source collection of C++ library code designed to augment
+the C++ standard library. The Abseil library code is collected from Google's
+own C++ code base, has been extensively tested and used in production, and
+is the same code we depend on in our daily coding lives.
+
+In some cases, Abseil provides pieces missing from the C++ standard; in
+others, Abseil provides alternatives to the standard for special needs
+we've found through usage in the Google code base. We denote those cases
+clearly within the library code we provide you.
+
+Abseil is not meant to be a competitor to the standard library; we've
+just found that many of these utilities serve a purpose within our code
+base, and we now want to provide those resources to the C++ community as
+a whole.
+
+<a name="quickstart"></a>
+## Quickstart
+
+If you want to just get started, make sure you at least run through the
+[Abseil Quickstart](https://abseil.io/docs/cpp/quickstart). The Quickstart
+contains information about setting up your development environment, downloading
+the Abseil code, running tests, and getting a simple binary working.
+
+<a name="build"></a>
+## Building Abseil
+
+[Bazel](https://bazel.build) is the official build system for Abseil,
+which is supported on most major platforms (Linux, Windows, macOS, for example)
+and compilers. See the [quickstart](https://abseil.io/docs/cpp/quickstart) for
+more information on building Abseil using the Bazel build system.
+
+<a name="cmake"></a>
+If you require CMake support, please check the
+[CMake build instructions](CMake/README.md).
+
+## Codemap
+
+Abseil contains the following C++ library components:
+
+* [`base`](absl/base/) Abseil Fundamentals
+  <br /> The `base` library contains initialization code and other code which
+  all other Abseil code depends on. Code within `base` may not depend on any
+  other code (other than the C++ standard library).
+* [`algorithm`](absl/algorithm/)
+  <br /> The `algorithm` library contains additions to the C++ `<algorithm>`
+  library and container-based versions of such algorithms.
+* [`container`](absl/container/)
+  <br /> The `container` library contains additional STL-style containers,
+  including Abseil's unordered "Swiss table" containers.
+* [`debugging`](absl/debugging/)
+  <br /> The `debugging` library contains code useful for enabling leak
+  checks, and stacktrace and symbolization utilities.
+* [`hash`](absl/hash/)
+  <br /> The `hash` library contains the hashing framework and default hash
+  functor implementations for hashable types in Abseil.
+* [`memory`](absl/memory/)
+  <br /> The `memory` library contains C++11-compatible versions of
+  `std::make_unique()` and related memory management facilities.
+* [`meta`](absl/meta/)
+  <br /> The `meta` library contains C++11-compatible versions of type checks
+  available within C++14 and C++17 versions of the C++ `<type_traits>` library.
+* [`numeric`](absl/numeric/)
+  <br /> The `numeric` library contains C++11-compatible 128-bit integers.
+* [`strings`](absl/strings/)
+  <br /> The `strings` library contains a variety of strings routines and
+  utilities, including a C++11-compatible version of the C++17
+  `std::string_view` type.
+* [`synchronization`](absl/synchronization/)
+  <br /> The `synchronization` library contains concurrency primitives (Abseil's
+  `absl::Mutex` class, an alternative to `std::mutex`) and a variety of
+  synchronization abstractions.
+* [`time`](absl/time/)
+  <br /> The `time` library contains abstractions for computing with absolute
+  points in time, durations of time, and formatting and parsing time within
+  time zones.
+* [`types`](absl/types/)
+  <br /> The `types` library contains non-container utility types, like a
+  C++11-compatible version of the C++17 `std::optional` type.
+* [`utility`](absl/utility/)
+  <br /> The `utility` library contains utility and helper code.
+
+## License
+
+The Abseil C++ library is licensed under the terms of the Apache
+license. See [LICENSE](LICENSE) for more information.
+
+## Links
+
+For more information about Abseil:
+
+* Consult our [Abseil Introduction](https://abseil.io/about/intro)
+* Read [Why Adopt Abseil](https://abseil.io/about/philosophy) to understand our
+  design philosophy.
+* Peruse our
+  [Abseil Compatibility Guarantees](https://abseil.io/about/compatibility) to
+  understand both what we promise to you, and what we expect of you in return.