The listview displaying Leads may be included in the Sales or Marketing module, depending on ASPEC Setup configured by the Administrator. 

Fig 1: Lead in the Sales module

The lead listview can also be viewed in the marketing module as it is related to Scope.

Columns in this Listview are configurable by each user.

This listview displays rows of data, based on the  Filter.  Usually, users do not want to look at all records.  Please read this post about filters, exports, and reports.