Search Engine Changes in SharePoint 2013

In this article, I have tried to capture the major changes between the SharePoint 2013 and SharePoint 2010 search engines.

	SharePoint 2013	SharePoint 2010
Code Base	The Search engine is a combination of SharePoint and FAST search engines (single code base) hence advanced capabilities that were earlier available for FAST Search deployments will now be available to SharePoint deployments.	There are two product lines – SharePoint Search and FAST Search (the code bases are different).  Examples of capabilities specific to the FAST Search for SharePoint are: Content-processing pipeline Metadata extraction Structured data search Deep refinement Visual search Advanced linguistics Visual best bets Extreme scale and performance
Logical Architecture	Addition of Content Processing, and Analytics Components. The components are: Crawer Content Processor Analytics Processor Indexer Query Processor The Search Administrator component runs many system processes required for search, is responsible for search provisioning and topology changes and coordinates search components – Content Processing, Query Processing, Analytics, and Indexing.	Crawler component was responsible for content/document processing. The components are: Crawler Indexer Query Processor/Server Administration is done through the Central Administration site.
Crawling	Anonymous crawling of http sites is possible. Continuous crawl for SharePoint content sources is available. Because of changes in how the index is created and stored, a document can appear in the index within seconds of going through the content processing component.	The Waiting period is long for index to merge and show results.
Result Sources	Specify a location to get search results from and specify a protocol for getting those results.	Functionality available by Federated Search and Scopes.
Analysis Engine	Run time analysis engine for a variety of jobs including ranking algorithms and recommendations. Search Analytics Link and Anchor text analysis Click Distance Search Clicks Deep Links Social Tags Social Distance Search Reports Usage Analytics Recommendations Usage Counts Activity Ranking	Web Analytics in Central Administration provides usability reports and administration reports that mentions latency, crawl throughput and so on.
End-User Experience	Direct access to the most granular information inside of sites and documents, and then enables users to act on the results without having to leave the results page. Every search box in every team site offers full access to enterprise-wide search, people search, and other specialized search experiences in addition to the traditional scoped site search	A user enters a set of search terms on a search center homepage that are treated as keywords, and the results are a single ranked list of links with three-line summaries and a little metadata.
Hover Panel	New in SharePoint 2013. Shows visual previews of sites, documents, and conversations. A new set of actions that users can perform right on the search result. For example, following a document, leaping right into Edit mode, or sharing or opening the library the document is stored in to see what other content is available.	Not Applicable
UI Framework	The UI framework that supports all these new features is re-designed. It is based on a set of nested layout templates that are defined in JavaScript and HTML for much easier extensibility.	SharePoint Server 2010 includes many search-related web parts for power users to create customized search experiences, including Best Bets, refinement panel extensions, featured content, and predefined queries.
Expertise Search	Document Authors are identified as experts based on the content mentioned in the document (Word, PowerPoint, PDF).	My Site profiles identifies expert in an area.
People Search	People Search is integrated with core results. People search can be targeted by name, location, phone number and other properties.	People Search is independent of document search.
Managed Properties	Organization specific dictionaries with custom entities can be mapped to managed properties.
Results Rendering Approach	Asynchronous client-side approach.	Server based rendering approach.
Query Rules	Query Rules are a new feature in SharePoint 13 that help act upon the "intent" of a query. Query Rules are composed of three top level elements: Query Conditions (i.e. matching rules), Query Actions (i.e. what do you do when you find a match). Publishing Options (i.e. when should this rule be active). Query Rules allows to have search requests from a user trigger multiple queries and multiple result sets.	Simple queries – one query has one set of results.
Document Parsing	New parsing features: Automatic file format detection Deep link extraction for Word and PowerPoint formats Visual metadata extraction: titles, authors and dates High-performance format handlers for HTML, DOCX, PPTX, TXT, Image, XML and PDF formats New Montage, Visio and OneNote filters The IFilter API continues to be supported as a means of extending the supported set of file formats	Document detection relies on file extensions