You can inspect variables in two ways: by moving the mouse over the name of a variable in the Debug editor window (hovering) or by using the Variables view. With hovering, the debugger displays the value of a variable in a tree structure in a small window that disappears when you move the mouse away from the name of the variable. While the debugger displays the window, you can expand and collapse the tree structure to view more information. However, you cannot edit the value of the variable. The debugger Variables view provides easy access to the variables in your program and enables you to observe and edit variables.
When a thread suspends, the top stack frame of the thread is automatically selected. When a stack frame is selected, the visible variables in that stack frame are displayed in the Variables view. Complex variables can be expanded to show the elements that make up the variable.
Variable values can be changed in the Variables view by clicking the value of the variable in the Value column and changing the value inline or by performing these steps:
To indicate that the variable value has changed, its indicator will have a delta symbol next to it. All variables affected by the change will also have a delta symbol next to their indicators.
The Variables view displays all variables for a selected stack frame. If you are debugging C/C++, local variables, not global variables, are displayed. If you are debugging assembler, current line operands are displayed. The view dynamically shows the variables in the current scope and they will appear and disappear as the program is stepped through or resumed. As an alternative to the Variables view, you can monitor variables in the Monitors view. In the monitors view, the debugger always shows the value for a variable if it can be obtained. To view and inspect one or multiple variables at a time, right-click the variable or variables and select Monitor Local Variable from the pop-up menu to work with the variables in the Monitors view.
Depending on the language that you are debugging, you can filter the Variables view to display certain variables only. To do this, right-click in the Variables view and select an entry from the Filter Locals submenu as shown in the following image.

From the variables view, you can set the value to be represented in either a decimal or hexadecimal (EBCDIC) format. To select the representation, highlight the variable, right-click, select Change representation and then the desired format:

Viewing the value in EBCDIC internal display may be useful when debugging data exceptions.