The Leads Module has several default views set up for you. Here is what each one displays:
Active Leads - Leads awaiting closure - These have neither been marked as dead, nor have they been converted. To ensure that this list is up to date, you can use the Check for Leads option, at the top of the list.
This should pull new leads to your list almost immediately. You will be notified via a visual notification about new incoming leads.
Converted Leads - These leads have been converted into a prospect account and optionally, an opportunity.
Dead Leads - Leads that closed and did not turn into an account.
Leads this Month - A list of leads that have been added to Operate within the current month.
New Leads - This list displays the most recent leads.
Today's Leads - A list of leads that have been added to Operate within the current day.
These are the default views; however, you can also create your own.