In the old days, Microsoft’s Visual Studio used to come with an offline package called MSDN which contained all the documentation about Visual Studio, its various development components and supporting programming languages. But now we have to depend on online documentation for everything.
If you want to browse through the documentations of various programming languages and development tools, then you can use an open-source software called Zeal. It is an offline documentation browser for Windows and Linux. For the macOS platform they point out another open-source project called Dash.
Zeal comes out like an empty shell without any documentation of any kind. You have to download and install the documentation if you want. First of all you have to make a selection for the documentation that you want. It offers a large number of documentations for various languages and development tools such as ActionScript, Android, Apache Server, Nginx, Bash, C, Cmake, C++, CSS, CoffeeScript, AppleScript, Drupal, HTML, Haskell, Java, Joomla, LaTeX, Mono, MySQL, Python, PHP, Ruby, SQLite, jQuery and many more. The total number of documentation sets offered by Zeal is 205 and it continues to grow.
The list of these available documentation sets can be accessed by launching Zeal, selecting Tools and then DocSets from the menubar. After selecting a documentation from the list, you can just click on the Download button. It will then download the selected documentation and then install it. Depending on the documentation type and the download size, it may take shorter or longer time to install it.
Once a documentation set is installed, we can access it from the Zeal window. You can either browse the whole documentation by clicking on it from the left side list of installed documentations, or you can try searching for something using the search box. If you have installed multiple documentation sets, then it will display an icon to indicate the documentation set in the results.
Zeal is a really useful tool to have for all the developers. It saves us from searching for every single thing online which might take more time and we might get distracted by many different things. It also offers some of the documentation sets that are not easily available otherwise.
You can download Zeal from https://zealdocs.org/.