CFS is a Multiple Document Interface (MDI) application. This means that you may have several windows open at the same time. The main CFS window is a container for all the MDI windows. There are three types of windows in the MDI: Section Window, Analysis Window, and Report Window.
Additionally there are two windows for defining inputs: Section Inputs and Analysis Inputs. These are `floating' windows that are displayed separate from the main CFS window. They may be moved outside the boundaries of the CFS window, and they may be closed and reopened at any time.
There are also several 'dialog' windows used for entering specific information to complete a task. Some examples are Section Wizard, Insert Ribs, Member Check Parameters, Web Crippling Parameters, and Analysis Wizard.
The main CFS window contains a menu of commands at the top. These commands are used to perform specific tasks, and are grouped into the categories: File, Edit, View, Compute, Tools, Windows, and Help. Many of the commands on these menus have shortcut keys which are displayed next to the command. Some of the menu commands are available in pop-up menus from the section window, analysis window, and input grids. A toolbar also provides quick access to many of the menu commands.
Many inputs throughout the application are numerical with an associated unit of measure. Initially, these inputs use the units defined by the application defaults (see Options - Units). These inputs contain a drop-down list showing conversions to other units of the same type. You may select any of the values in the list, thereby changing the default unit for that specific input. You may also type in the value and the unit you want to use. If you start modifying an input and change your mind, you may press the Esc key to revert to the previous value.
Several input windows contain multiple tabs. Click on a tab to change the displayed tab. You may also use the Ctrl-Tab and Ctrl-Shift-Tab keys, or Ctrl-Page Up and Ctrl-Page Down keys, to cycle through the pages.
Many of the inputs for sections and analyses are organized in a tabular form, or grid. Grids behave very similar to spreadsheets. By positioning the cell pointer on the desired location, you may change the entry by just retyping it, or by editing it. An input can be made available to edit by either double-clicking on it or by pressing F2. Rows in a grid may be inserted, deleted, copied, pasted, etc.
Several keys may be used for navigation and cell selection in a grid. Arrow keys, Page Up, Page Down, Home, and End all move the cell pointer around the grid. Using the arrow keys while holding the Shift key extends the selection of cells. Ctrl-X, Ctrl-C, and Ctrl-V are used to cut, copy, and paste rows.