# 3 Overview

#### Overview

The *Monitoring → Overview* section offers an overview of trigger states
or a comparison of data for various hosts at once.

The following display options are available:

-   select all hosts or specific host groups in the *Group* dropdown
-   choose what type of information to display (triggers or data) in the
    *Type* dropdown
-   select horizontal or vertical display of information in the *Hosts
    location* dropdown

**Overview of triggers**

In the next screenshot Triggers are selected in the *Type* dropdown. As
a result, trigger states of two local hosts are displayed, as coloured
blocks (the colour depending on the state of the trigger):

![](../../../../../assets/en/manual/web_interface/overview_triggers.png){width="600"}

Note that recent trigger changes (within the last 30 minutes) will be
displayed as blinking blocks.

Blue up and down arrows indicate triggers that have dependencies. On
mouseover, dependency details are revealed.

Clicking on a trigger block provides links to trigger events,
configuration, the acknowledgement screen, URL or a simple graph/latest
values list.

![](../../../../../assets/en/manual/web_interface/overview_links2.png)

**Overview of data**

In the next screenshot Data is selected in the *Type* dropdown. As a
result, performance item data of two local hosts are displayed.

![](../../../../../assets/en/manual/web_interface/overview_data.png){width="600"}

Only values that fall within the last 24 hours are displayed by default.
This limit has been introduced with the aim of improving initial loading
times for large pages of latest data. It is also possible to change this
limitation by changing the value of ZBX\_HISTORY\_PERIOD
[constant](/fr/manual/web_interface/definitions) in
*include/defines.inc.php*.

Clicking on a piece of data offers links to some predefined graphs or
latest values.

![](../../../../../assets/en/manual/web_interface/overview_links.png)