T

Table

A set of data elements that has a horizontal dimension (rows) and a vertical dimension (columns) in a relational database system. A table has a specified number of columns but can have any number of rows. A table is often called a relation. Rows stored in a table are structurally equivalent to records from flat files in that they must not contain repeating fields.

Table of Contents

In ArcMap, the table of contents lists all the data frames and layers on the map and shows what the features in each layer represent.

Target Layer

Used in ArcMap editing, a setting in the Target Layer dropdown list that determines to which layer new features will be added. The target layer is set by clicking a layer in the Target Layer dropdown list. For instance, if you set the target layer to Buildings, any features you create will be part of the Buildings layer. You must set the target layer whenever you're creating new features-whether you're creating them with the Sketch tool, by copying and pasting, or by buffering another feature.

Template

The Template tool helps users produce designs more efficiently. The user creates a template for frequently performed tasks, such as a service drop to a residence. The template would contain the same features in the same order, while the only modification would be their positioning in the network.

Text Symbol

A text style defined by font, size, character spacing, color, and so on, used to label maps and coverage features in ArcInfo.

Thumbnail

A snapshot describing the geographic data contained in a data source or layer, or a map layout. A thumbnail might provide an overview of all the features in a feature class or a detailed view of the features in, and the symbology of, a layer. Thumbnails are not updated automatically; they will go out of date if features are added to a data source or if the symbology of a layer changes.

Tie Device/Tie Point

Tie devices, or tie points, are defined as switchable devices that are set in an "open" state and energized from two directions at once. Feeder Manager allows you to select all tie devices and filter the selection down to those devices associated with a given feeder or group of feeders.

Toolbar

A set of commands that lets you carry out related tasks. The Main Menu toolbar has a set of menu commands; other toolbars typically have a set of buttons. Toolbars can float on the desktop in their own window, or you can dock them at the top, bottom, or sides of the main window.

Tracing

The process of determining which portions of a network connect.