What is site and site collection is Sharepoint? And What is the main advantage of using site collections?
Share point is all about enterprise data. When we talk about enterprise data it looks some as shown in the figure below. In other words grouping and sub groupings of data.
SharePoint extends the IIS web application structure to accommodate the above defined data structure using site and site collections.
Advantages of using Site Collections
SharePoint is all about data and data should properly authenticated / authorized to proper users. By defining the structure in site and site collection we can now define roles and responsibilities according to data. For instance in the above figure we will assign all HR user to payroll, recruitment and assessment site. These users will not be assigned to account site collection. Same holds true for accounts user.
So when you design your hierarchy of site and site collection you need to keep in mind the enterprise hierarchy structure and design the same accordingly.
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