OLAP stands for On-Line Analytical Processing. OLAP solutions allow the user to quickly analyze information that has been summarized into multidimensional views and hierarchies, OLAP based systems being successfully used in business intelligence and business performance management applications.
The core of an OLAP application is the OLAP cube. The arrangement of data into cubes overcomes a limitation of relational databases. Relational databases are not well suited for near instantaneous analysis and display of large amounts of data.

The added value of a business intelligence application is the decisional support offered by the information that you obtain from the system (from your OLAP cubes). How do you get the information? The answer is simple: analysis, reports or more complex dashboards. I would categorize reporting tools in two main categories: reporting servers and ad-hoc analysis tools. From a reporting server you would expect automatic report generation and schedule report generation both options based on a predefined set of reports, possibility to group reports into batches, security level of access to reports, report delivery by email, various export option, import/export of report definitions. In this case the reports would be previously developed by a trained person. Ad hoc analysis tools are more oriented to quickly deliver the necessary information allowing the instant access through a simple 1 minute drag a drop wizard, that could be used by any business user.