The Text property specifies the control's text/expression. The Expression property returns the expression to be evaluated. The EvaluateSelection property specifies whether the control evaluates the selection when it is available. So, if the EvaluateSelection property the Expression property returns the selected text ( if the SelLength property is greater than 0 ), or the entire text if the SelLength property is 0. The control fires the SelChange event when user changes the selection. Use the SelForeColor and SelBackColor properties to specify the colors for the selected text.

For instance:

• the currency(value) displays the value using the current format for the currency ie, 1000 gets displayed as $1,000.00, for US format
• the longdate(date(value)) converts the value to a date and gets the long format to display the date in the column, ie #1/1/2001# displays instead Monday, January 01, 2001
• the '<b>' + ((0:=proper(value)) left 1) + '</b>' + (=:0 mid 2) converts the name to proper, so the first letter is capitalized, bolds the first character, and let unchanged the rest, ie a "mihai filimon" gets displayed "Mihai Filimon".
• the value format '2|.3|,' displays the value using 2 digits, . as decimal separator, grouping by 3 digits using the , as a grouping separator. 
• the type(value) in (0,1) ? 'null' : ( dbl(value)<0 ? '<fgcolor=FF0000>'+ (value format '2|.|3,' ) : (dbl(value)>0 ? '<fgcolor=0000FF>+'+(value format '2|.|3,' ): '0.00') ) displays the positive values in blue, being preceded by + sign, negative values in red preceded by - sign, 0 as 0.00 while for null values is displays null. The numbers are displayed using 2 digits, . as decimal separator and grouping by 3 digits by , separator.
• the ((1:=int(0:= (value))) != 0 ? (=:1 + ' day(s)') : '') + (=:1 ? ' ' : '' ) + ((1:=int(0:=((=:0 - =:1 + 1/24/60/60/2)*24))) != 0 ? =:1 + ' hour(s)' : '' ) + (=:1 ? ' ' : '' ) + ((1:=round((=:0 - =:1)*60)) != 0 ? =:1 + ' min(s)' : ''), displays the value in days, hours and minutes

Most of our components support formatting the values. By formatting we mean that instead displaying a  value we can display in the way we desire. Properties such as Column.FormatColumn, Items.FormatCell and so on support formatting. For instance, the currency(100) displays the value 100 as a currency, for instance in US format it will display $100 while for German format will display 100 €. The format expression supports operators, constants and values as described bellow. From case to case, there are few predefined keywords such as value, which indicates the value to be formatted, the %0, %1, %2, %3, ... indicates variables that could be: the value in a specified column, the value for a specified property of the bar, and so on. If the formatting is using in  properties such as: Items.ItemBar(exBarToolTip), Items.ItemBar(exBarCaption) or Items.ItemBar(exBarExtraCaption) the %C0, %C1, %C2, ... indicates the captions of the cells, ...

This property/method supports predefined constants and operators/functions as described here.