| Profusion | WebCrawler | Highway 61 | Metacrawler | |
|---|---|---|---|---|
| Duplicate Detection | Yes | [NA]1 | Yes | [NA] |
| Relevancy Ranking | Yes | Yes | Yes | Yes |
| Proximity or Phrase | Phrase, w/o punctuation | Phrase, proximity (ADJ, NEAR/x) | [Phrase] | Phrase |
| Case Sensitive | Yes | [No] | [NA] | [No] |
| Truncation | Right-hand; internal | [No] | [Right-hand] | [Right-hand] |
| Boolean Logic | AND (&), OR (|), NOT (!), NEAR (~); can nest | AND, OR (default), NOT; can nest | AND (default), OR | AND, OR (default) |
| Other Limiters | Search Web or Usenet | -- | + | + -, length of time for search |
| Retrieval Display Options | With or w/o summary | Titles or summaries | No. of hits returned | Results per page; returns sortable by relevance, domain, keyword, or source |
| Type (and no.) of Engines Queried | Keyword (6), Concept (1), Subject Index (2) | [NA] | Keyword (3), Subject Index (1), Concept (1) | Keyword (4), Subject (2), Meta (1), Concept (1) |
1Information Not Available from engine's web pages.
2Information supplied by this author after personal use of the engine.