ArcView 3.x terminology (Projects, Views, Themes, Layouts, etc.)

In a nutshell:

Views are visual displays of the highlighted themes of data sets.

Tables display the attributes of data sets.

Charts are visual displays of selected attributes of data sets.

Layouts are composites of views, tables, charts, legend material and title text.

Scripts provide a way to modify the standard ArcView interface.

Projects contain related views, tables, charts, layouts, and scripts.

Projects

A "project" is the mechanism by which views, scripts, layouts, and other work done on a particular problem are kept together within ArcView. You can think of it as a manila folder. To the user, opening a 'project' is like opening a file in any other application. A project file points to certain data sets, and selected data within them, without itself containing the data (thus project files are typically quite small). The project file contains the instructions necessary for ArcView to recreate saved views, plots or charts of the data when the project is opened. Because a project file typically points (with a path) to external data sets and requires them to generate views or plots, if a project file is moved to another computer, the paths to the data may have to be adjusted for the project file to function in its new location.

Data Sets

Data sets useable with ArcView are of two basic types: those which have embedded geometric (coordinate) information, and those which have no embedded geometric information, but instead an attribute which can be used to link the data set to one which does have geometric information. In metadata parlance, these two types of data have 'Direct Spatial Reference' and 'Indirect Spatial Reference,' respectively.

Examples of data sets with embedded geometric information are Arc/Info coverages, shapefiles, TIF images with associated world files, or ERDAS .LAN or .IMG (usually satellite or remote sensing imagery) files. The geometric information usually provides x and y values in one of a group of standard coordinate systems, such as latitude-and-longitude, Universal Transverse Mercator (UTM) or State Plane Coordinates (SPC). The geometric information may describe points, lines, polygons, or grid data. These are the sort of data sets one would use to create a graphic recognizable as a map. Typically these data sets also contain some attribute information; in the case of a coverage consisting of tax parcel polygons an expected attribute would be something like the parcel identification number.

Examples of Indirect Spatial Reference data sets include tabular data such as INFO files, .dbf (database) files, and comma delimited ASCII files with an attribute that allows them to be related to another data set with Direct Spatial Reference. A specific example might be a tax revenue data set which includes owner information and a parcel identification number to link it to the tax parcel coverage mentioned above. Indirect Spatial Reference data sets cannot be used alone to produce a map (because they do not contain the necessary geometric information), but they could be used alone to produce a chart.

Data sets may have many attributes and as a result each geometric object in Direct Spatial Reference data will also. One or more attributes from a data set are used to create the themes of a view.

Views

A view is a window display of selected themes. In general terms, it is a "map." For a useful view, it is necessary that it contain at least one selected theme.

It is possible to set the projection or coordinate system of a view if the geometric data is in decimal latitude/longitude form. A view cannot be printed directly, but it can be printed indirectly by placing it into a layout and printing the layout.

Themes

A theme is created when a particular attribute of a data set is chosen and used to set the graphical presentation (color, pattern, size) of the geometric component of the data set. A single data set may be used to create several themes. A theme is selected (and will be drawn) when a check mark appears in the box next to the theme title. A theme is 'active,' and may have its properties set (e.g. that the theme is only visible in a view at certain scales) when it appears raised in the themes window. Double-clicking on a theme title brings up the legend editor which can be used to set the theme name and the symbol type and color for the theme. Any individual theme is drawn on top of, and may obscure, any themes listed below it in the themes window.

Tables

The 'virtual table' capabilities of ArcView Tables give this module great flexibility. Essentially, a virtual table is a view of tabular data which can be saved in a project. It is possible to rearrange the order of fields in a table, hide fields, give aliases to field names, sort columns, and attach tables to one another 'virtually,' i.e. without actually creating any new tables, or editing the underlying tables. A virtual table may be exported to create a 'real' table. A query tool in tables allows records to be selected based on logical expressions. If the selected records are tied to spatial data (points, lines, or polygons) in a view, they will also will also be shown as selected in the view

Charts

Charts gives ArcView the capability to show tabular information graphically in forms other than a map. ArcView can produce six types of charts: area, bar, column, line, pie, and xy scatter.

Layouts

Layouts are the mechanism by which the visual components of an ArcView project are arranged on a 'page' for presentation on screen or in preparation for printing or exporting. Views and their legends, charts, tables, scale bars, north arrows, title and explanatory text are all possible components of an ArcView layout.

Scripts

Scripts provide a way to customize the standard ArcView environment or to automatically carry out functions one might otherwise do manually through built-in ArcView functions. They provide a way to build a simplified user environment into a project file. Scripts can be assigned to (and run from) the menu bar, to icons on the button or tool bars, or the project window. The properties of a project can be set to run specific scripts when the project starts up or shuts down.

The scripting language for ArcView, Avenue, is an object based language. The ArcView interface itself is built from Avenue scripts. All of these system scripts are available for the user to look at as examples of Avenue programming and to modify into their own specialized scripts if desired. Before you write a complex Avenue script from scratch, you might want to look at documented user contributed scripts available for download from ESRI.