There are quite a few modules which help in making it easier to tag the content on a site.
Some of these are completely internal, some rely on free (or "freemium") third party services, some rely on fee-based third party services. Some provide UI enhancements and some are transparent to the end user.
| Name | Releases | Description | Usage (Aug 1st) |
|---|---|---|---|
| OpenCalais | 6.x stable, 5.x stable | Uses the free but rate limited third party Calais term extractor to automatically tag content. | 4,739 |
| Yahoo Terms | 6.x stable | Uses the free, but rate limited Yahoo term extraction service to automatically tag content. | 46 |
| Inform | 6.x dev | Uses the commercial Inform service to automatically tag content. | 0 |
| Amplify | 6.x stable | Uses the commercial Amplify service to analyze content (doesn't store them as terms yet (Developer use is free, production use is not) | 63 |
| Auto Tagging | 6.x beta | A generalized system to leverage multiple backends for automatically tagging. Currently supports OpenCalais, Yahoo! terms extraction, TagThe.net. | 131 |
| Tagging | 6.2.4 stable | Advanced UI, API to implement suggestions (OpenCalais, Alchemy or Extractor for sematic content suggestions allready implemented) | 905 |
| Extractor | 6.x alpha | Uses a vocabulary to look up terms in any given text. Integrates with Feeds where it's used to extract terms from imported content. Node independent. | 808 |
| Taxonomy Autotagger | 6.x stable | A UI improvement which also suggests terms based on the content of the node and an existing vocabulary. | 219 |
| Autocategorise | 6.x stable | Automatically tags based on a defined vocabulary and the content of the title/body of a node. | 92 |
| HILCC Taxonomy Autotag | 6.x dev | Auto-generates HILCC (Hierarchical Interface to the Library of Congress Classification) taxonomy terms for nodes that have LCC call numbers (library-assigned numbers like "QA 76.73 .P224 2005"). | 12 |
| Keyword Analysis | 6.x | Does both Yahoo! term extraction and based on frequency analysis | 75 |
| Alchemy | 6.x | Integrates with the free (limited to 30,000 calls/day) Alchemy service for extraction of keywords, entities and concepts. Integrates with Content Analysis, Tagging and Auto Tagging modules. | 75 |
| Suggested Terms | 6.x stable, 5.x stable | Provides "suggested terms" for free-tagging Taxonomy fields based on terms already submitted. Adds suggested terms that can be clicked to add to the default autocomplete field. | 1,005 |
| Active Tags | 6.x stable | While the primary module provides a widget for adding tags to a freetagging vocabulary, a sub-module adds suggested terms based on the most-used existing terms in the given vocabulary. | 2,958 |
Please update descriptions and/or add more modules as you see fit.