They don't provide any executables, DLLs or other binaries... just the source code for the programmer to compile in their programming environment.
For Production Use Source code tarballs of the official releases can be downloaded from www.openssl.org/source. The OpenSSL project does not distribute the toolkit in binary form.
However, for a large variety of operating systems precompiled versions of the OpenSSL toolkit are available. In particular on Linux and other Unix operating systems it is normally recommended to link against the precompiled shared libraries provided by the distributor or vendor.
For Testing and Development Although testing and development could in theory also be done using the source tarballs, having a local copy of the git repository with the entire project history gives you much more insight into the code base.
The official OpenSSL Git Repository is located at git.openssl.org. There is a GitHub mirror of the repository at github.com/openssl/openssl, which is updated automatically from the former on every commit.
A local copy of the Git Repository can be obtained by cloning it from the original OpenSSL repository using
git clone git://git.openssl.org/openssl.git or from the GitHub mirror using
git clone https://github.com/openssl/openssl.git If you intend to contribute to OpenSSL, either to fix bugs or contribute new features, you need to fork the OpenSSL repository openssl/openssl on GitHub and clone your public fork instead.
git clone https://github.com/yourname/openssl.git This is necessary, because all development of OpenSSL nowadays is done via GitHub pull requests. For more details, see Contributing.
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