First you should know What is Sharepoint Server Farm??

SharePoint Server Farm includes many servers or as few as two servers. A Sharepoint Server farm divided in to three categories: SMALL, MEDIUM, LARGE. You can choose one category as per your requirement. 

Front End Web Server: The Web server role provides Web content to clients.

Front End Application Server: The application server role provides Office Sharepoint Server 2007 services such as servicing search queries, and crawling and indexing content.

SQL Database Server:  SQL Database Server save all content of SharePoint sites etc.

Domain controller: Through this we can provide authorization and authentication services to users.

Small server farm consists of two-server, one servers hosts the Web front end and the application services, while the second server hosts the SQL Server database.

A medium server farm consists of a database server, an application server Running Office Sharepoint Server 2007, and one or two front-end Web servers running Office SharePoint Server 2007 and IIS.

A large server farm consists of two or more clustered database servers, several  front-end Web servers running Office SharePoint Server 2007, and two or more application servers running Office SharePoint Server 2007.

If data of SharePoint Server farm get corrupted then it can be happen due to two main causes like:

1. SQL Server Database get corrupt
2. SharePoint Site get inaccessible

Due to this, you are not able to perform lots of activities such as:

SharePoint Inbuilt utilities helps you to recover corrupt SharePoint data like

1. stsadm.exe
2. Central Administration user interface
3. SQL Server backup

But Sometimes these utilities are not able to perform complete SharePoint data recovery. In this case, I have another suggestion that is use of SharePoint Server Recovery Software. These Software’s recover data in most of the SharePoint corruption error conditions. No matters how big the farm, Software also recovers data from SharePoint Server Farm.