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SharePoint Foundation Service :- The core SharePoint service for content collaboration. In large SharePoint Server 2010 deployments, we recommend that you allocate redundant Web servers based on expected traffic load, properly size the SQL Server–based computers that service the content databases, and properly allocate storage based on the size of the farm.

Central Admin Service:-  The administration service. This service has relatively small capacity requirements. We recommend that you enable this service on multiple farm servers to ensure redundancy. 

 Logging Service:-  The service that records usage and health indicators for monitoring purposes. This is a write-intensive service, and can require relatively large disk space depending on the number of indicators and the frequency at which they are logged. In large SharePoint Server 2010 deployments, we recommend that you isolate the usage database from the content databases on different SQL Server–based computers.

SharePoint Search Service Application:-  The shared service application that provides indexing and querying capabilities. Generally this is a relatively resource intensive service, that can scale to serve very large content deployments. In large SharePoint Server 2010 deployments where enterprise search is very important, we recommend that you use a separate “service farm” to host search service applications, with dedicated database resources, use multiple application servers servicing specific search functions (crawl or query), and dedicated target Web servers on the content farms to ensure acceptable throughput for crawling and querying. You can also enable the FAST Service Applications as your Search Service Application. Choose to create one or more FAST Search Connectors for indexing content with FAST Search Server 2010 for SharePoint and create another FAST Search Query (SSA) for querying content that is crawled by the FAST Search Connectors.

Word Viewing Service Application:-  Enabling this service lets you view Word documents directly from the browser. This service is added when you install Office Web Apps in addition to SharePoint Server 2010. This service requires an application server to prepare the original files for browser viewing. In large SharePoint Server 2010 deployments, we recommend that you scale out the service to multiple application servers for redundancy and throughput. Note: Browser editing for Word and OneNote are enabled when you install Office Web Apps on the SharePoint Server 2010 farm. However, this feature runs on the farm Web servers and does not use any service applications.

PowerPoint Service Application:- This service displays and lets users edit PowerPoint files directly in the browser, and also enables you to broadcast and share live PowerPoint presentations. This service is added when you install Office Web Apps on SharePoint Server 2010. This service requires an application server to prepare the original files for browser viewing. In large SharePoint Server 2010 deployments where this becomes a frequently used capability, we recommend that you deploy multiple application servers to ensure acceptable redundancy and throughput, and add more Web servers when PowerPoint Broadcast is frequently used as well.

Excel Calculation Service Application:- This service displays Excel worksheets directly in the browser and performs Excel calculations on the server. It also enables editing of worksheets directly from the browser when you install Office Web Apps on SharePoint Server 2010. In large SharePoint Server 2010 deployments where this becomes a frequently used capability, we recommend that you allocate a sufficient number of application servers that have sufficient RAM to ensure acceptable performance and throughput.

PowerPivot for SharePoint:- The service to display PowerPivot enabled Excel worksheets directly from the browser. In large SharePoint Server 2010 deployments where this becomes a frequently used capability, we recommend that you allocate a sufficient number of application servers that have sufficient RAM and CPU to ensure acceptable performance and throughput. For more information, see Hardware and Software Requirements (PowerPivot for SharePoint).

Visio Service Application:-  The service to display dynamic Visio diagrams directly in the browser. This service has a dependency on the Session State Service Application, which requires a relatively small SQL Server database. The Visio service requires an application server to prepare the original Visio files for browser viewing. In large SharePoint Server 2010 deployments where this becomes a frequently used capability, we recommend that you scale out the service to multiple application servers that have sufficient CPU and RAM to ensure acceptable performance and throughput. 

 Access Service Application:- The service to host Access solutions inside SharePoint Server 2010. In large SharePoint Server 2010 deployments where this becomes a frequently used capability, we recommend that you scale out to multiple application servers that have sufficient RAM for acceptable performance and throughput. The Access service uses SQL Reporting Services, which will require a SQL Server database that can be co-located with other databases.

User Profile Service Application:- The service that powers the social scenarios in SharePoint Server 2010 and enables My Sites, Tagging, Notes, Profile sync with directories and other social capabilities. The profile service requires three relatively resource intensive databases: the synchronization, Profile, and Social Tagging databases. This service is dependent on the Managed Metadata Service Application. In large SharePoint Server 2010 deployments, you should consider distributing this service to a shared services farm, and correctly size the database server tier to ensure acceptable performance of the common transactions and directory synchronization jobs.

Managed Metadata Service Application:- The service that powers the central metadata store and allows the syndication of content types across the enterprise. The service can be federated to a dedicated services farm. It requires a database that can be co-located with other databases.

Web Analytics Service Application:-  The service that aggregates and stores statistics on the usage characteristics of the farm. This service has relatively high SQL Server resource and storage demands. The service can be federated to a dedicated services farm. In large SharePoint Server 2010 deployments, we recommend that you isolate the Web Analytics databases from other very important or resource intensive databases by hosting them on different database servers.

Business Connection Service Application:- The service that enables the integration of various organizational line-of-business applications together with SharePoint Server 2010. This service requires an application service to maintain data connections to external resources. In large SharePoint Server 2010 deployments where this is a frequently used capability, we recommend that you allocate a sufficient number of application servers that have sufficient RAM for acceptable performance.

InfoPath Forms Service Application:- The service that enables browser-based forms in SharePoint Server 2010 and the integration with the InfoPath client application for form creation. This service requires an application server and has a dependency on the Session State Service Application, which requires a relatively small database. This service can be co-located with other services and has relatively small capacity requirements that can grow depending on the frequency of use of this capability.

Word Automation Service Application:- The service that enables conversion of Word files from one format, such as .doc, to another format, such as .docx or .pdf. This service requires an application server. In large SharePoint Server 2010 deployments where this becomes a frequently used capability, we recommend that you scale out the service to multiple application servers that have sufficient CPU resources to achieve acceptable conversion throughput. This service also requires a relatively small database to maintain the queue of conversion jobs.

PerformancePoint Service Application:- The service that enables PerformancePoint BI capabilities in SharePoint Server 2010 and enables you to create analytic visualizations. This service requires an application server and a database. In large SharePoint Server 2010 deployments where this becomes a frequently used capability, we recommend that you allocate sufficient RAM to the application servers for acceptable performance and throughput.

Project Service Application:- The service that enables all the Microsoft Project Server 2010 planning and tracking capabilities in addition to SharePoint Server 2010. This service requires an application server and a relatively resource intensive database. In large SharePoint Server 2010 deployments where this is a frequently used capability, you should dedicate a database server for the Project Server database and even consider a dedicated SharePoint Server 2010 farm for the Project Server management solutions.

Timer Service:- The process responsible of executing the various scheduled tasks on the different servers in the farm. There are various timer jobs that the system executes, some running on all farm servers, and some running only on specific servers depending on the server’s role. Some of these timer jobs are resource intensive and can potentially create load on both the local server and the database servers, depending on their activity and how much content they are operating against. In large SharePoint Server 2010 deployments where timer jobs can potentially impact end-user latency, we recommend that you dedicate a server to isolate the execution of the more resource intensive jobs.

Workflow :- The capability that enables integrated workflows in SharePoint Server 2010, and executes workflows on the Web server. Resource utilization is dependent on the complexity of the workflows and the total number of events they handle. In large SharePoint Server 2010 deployments where this is a frequently used capability, you should consider adding Web servers or isolating a server to handle only the workflow timer service to ensure end-user traffic is not affected and that workflow operations are not delayed.

Sandboxed Solutions:- The service that enables isolation of custom code to dedicated farm resources. In large SharePoint Server 2010 deployments where this becomes a frequently used capability, you should consider dedicating additional Web servers if custom code begins to impact server performance.