In general, you should only install modules from drupal.org. Stable module releases (i.e. those that don't have an "alpha" or "beta" appended to them) are monitored by the Drupal security team. For a module to be posted, it has to meet the Drupal coding standards. Neither of these is sufficient to guarantee that bad things won't happen when you install the module (including consequences potentially as bad as deleting things from your database), but that happens rarely.

That said, posting a module to drupal.org comes with certain administrative hurdles, such as having to do a code review for a certain number of other modules before you can even submit your own module for review. Posting modules to drupal.org is not always feasible for the digital humanities projects that develop them, particularly if they were funded by one-time grant money. These projects still may want to disseminate their module development work, and one common place to do that is Github, a code repository. Github may also be used to distribute "feature" modules (modules created using the Features module, which packages up configuration like content types into modules that can be installed to recreate that configuration on another site); see chapter 15 for more about Features.

Use caution when installing modules from Github, particularly modules that are not features. You should have reason to trust the developer before you install one of their modules (e.g. because they're affiliated with a digital humanities center). Agile Humanities Agency is one company that specializes in digital humanities development, and has done extensive work developing new modules for digital humanities use (like a Harris Matrix Viewer for archaeologists), and improving existing modules (like Partial Date and Editview).

Installation process

• Go to an individual Github repository, like the ones linked above.
• First, click on the "Clone or Download" button.
• Then, right-click (or control-click on Mac) on the "Download Zip" button that will appear.
• Choose "Copy link address" from the options that come up in your browser
• Paste the link address into the "Install from a URL" field on the module installation page (Modules > Install new module or /admin/modules/install), just as if you'd copied a .tar.gz or .zip link from drupal.org

Alternately, you can just download the zipped files from Github by clicking on "Download Zip", then upload that zipped package to your Drupal site.