Script is a program written in a higher-level language, which is a part of a report. As a report runs, the script runs as well. A script is able to perform data handling, which cannot be performed via regular means of the FastReport core, for example, to hide useless data according to any predefined condition. The script is also used for controlling properties of dialogue forms, which are the components of the report.

The script should be written using one of the languages, which are the components of the script engine (FastScript). Currently, the following languages are supported:

- PascalScript
- C++Script
- BasicScript
- JScript

The following FastScript features available in the script engine:
- standard language set: variables, constants, procedures, functions (with nesting capability) with variables, constants, default parameters, all standard operators (including case, try, finally, except, with), types (integral, fractional, logical, character, line, multidimensional arrays, set, variant), classes (with methods, events, properties, indexes, and default properties);
- declarations of the following types absent: records, classes in the script; no records, no pointers, no sets (however, the 'IN' - "a in ['a'..'c','d']" operator usage is possible), no shortstring type, no unconditional jump (GOTO);
- types’ compatibility checking;
- ability to access any report’s object.

You can create scripts in the FastReport designer, which contains the scripts’ editor with syntax’s highlighting. Also there is an embedded debugger, which possesses the following functions: "Step," "Breakpoint," "Run to cursor," and "Evaluate."