When a Filter is applied to a View, specific criteria within the Filter allow only the Tasks/Resources that meet those criteria to be met. Filters can also be applied to Tables and Reports.
In Project 2000, you can also apply a Filter to the Network Diagram View.
All filters can be applied by selecting the Pulldown menu from the Formatting Toolbar and clicking each in turn:-

Another way to access filters is by selecting them from Project | Filtered For

Only one Filter can be applied at a time. Note that the All Tasks Filter is used to “show all” that is, remove any filters previously selected. In addition, TASK filters cannot be applied to RESOURCE views and vice-versa.
Some of the most often used Filters are:-
Critical. Shows only critical tasks
Date Range. A dialog box requests a Start date and a Finish date. Only the tasks fall within OR traverse those dates will be shown.
Milestones. Shows only Milestone Tasks
Summary. Shows only Summary Tasks
Task Range… A dialog box requests two tasks ID numbers, only the tasks within, and including, these numbers will be shown
Using Resource… A Pull-Down Menu will all the selection of a Resource Name, only tasks to which this resource is assigned will be shown.
Using AutoFilters
These operate in a similar manner to “normal” filters as described above, with the main difference being that they are accessed via any Table or Sheet view column Header. They can be applied either from the pull-Down Menu as before, or from the same symbol as shown on the Toolbar (as before):

Once selected via either of the above, this is will result in the Table or Sheet having the following applied (as an example, the Entry Table is shown):

As shown above, any of the column headings can be pulled down via the menu arrow, and for example, only tasks to be shown for tasks greater or less than a day or week. Alternatively, only tasks of a certain Duration say, 5 days.
In addition, the (Custom…) selection can be made and the Custom Auto Filter dialog box is used to set certain criteria ( in the example above, only those tasks that are 4 days in duration AND are non-critical (Free Slack).
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