In the Anaconda repository, there are two types of installers:
\"Anaconda installers\" and \"Miniconda installers\".
What
The 2 in Anaconda2 means that the main version of Python will be 2.x rather than the 3.x installed in Anaconda3. The current release has Python 2.7.13.
The 4.4.0.1 is the version number of Anaconda. The current advertised version is 4.4.0 and I assume the .1 is a minor release or for other similar use. The Windows releases, which I use, just say 4.4.0 in the file name.
Others have now explained the difference between Anaconda and Miniconda, so I'll skip that.