Not For Sale. Glossary

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1 Glossary Actor A sprite and the role it plays as it interacts with another sprite on the stage. Animated GIF A graphic made up of two or more frames, each of which is displayed as an automated sequence when the GIF file is displayed. Argument Input received by a script for processing. Backdrop A background image displayed on the stage. Backpack An area on the Scratch Project Editor that moves resources between projects. Bitmap A type of graphics image saved as a collection of pixels that, when drawn, lay out a graphic. Blocks palette The area on the Scratch Program Editor where categories of code blocks are displayed. Boolean Data that has either of two values: true or false. Boolean block A code block that returns a Boolean value that has angled sides and can only be embedded inside other code blocks that contain an input area whose sides are also angled. Brightness The application or restriction of the intensity of light in a graphics image. Broadcast message An electronic message sent between sprites as a means of coordinating application activity. Not For Sale E-415

2 E-416 Glossary Not For Sale C block A code block shaped like the letter C that sets up a loop of blocks within scripts that repeatedly execute for as long as a tested condition evaluates as being true. Cap block A code block with a notch on the top and a flat bottom that halts the executions of scripts. Clone A copy of a sprite that is created and destroyed during script execution. Cloud variable A variable stored on the Scratch server on the Internet that is persistent across repeated executions of a project. Code block A graphical command used in the creation of a script. Collision An event that occurs whenever two sprites come into contact with one another on the stage. Comment A piece of text embedded as part of a script that describes its construction or operation. Compression The process of reducing the size of sound and graphics files to reduce the overall size of Scratch applications. Conditional logic The process of executing sets of code blocks based on whether or not a tested condition proves true. Control blocks A category of code blocks in Scratch 2.0 used to perform conditional logic, pause or halt script execution, set up loops, and create clones. Costume An image that represents a sprite on the stage or changes the sprite s appearance. Data A piece of information collected, stored, modified, and processed during application execution. Data blocks A category of code blocks in Scratch 2.0 that can be used to store data and lists used by applications when they execute. Debugger A program or utility that can execute an application within a special environment and allows programmers to slow and monitor the execution of an application s script as it runs. Decimal A floating point or real number. Endless loop A loop that does not have a means for terminating its execution. Event handling The process of initiating script execution based on the occurrence of predefined events, such as a mouse click, the pressing of a keyboard key, and the clicking of a sprite. Events blocks A category of code blocks in Scratch 2.0 that initiate the execution of scripts and send broadcast messages.

3 Glossary E-417 Fisheye A graphics effect that can be applied to a sprite or background to magnify a portion of its image. Forum Publicly shared discussions hosted by the Scratch 2.0 website in which Scratchers can discuss topics of common interest. Ghost A graphics effect that fades the appearance of a costume or background, making it look transparent. Global variable A variable that any script in an application can modify. Gradient A color created by blending the foreground and background color. Hat block A code block that creates event-driven scripts. IDE (Integrated Development Environment) A graphical application development environment designed to facilitate program development. Integer An absolute or whole number that does not have a decimal point. Java A popular web-based programming language that is a prerequisite to executing a Scratch application on the Scratch website. Kinect2Scratch Collects and processes sensory data captured using a Microsoft Kinect controller attached to your computer. LEGO Education WeDo Robotics Kit A robotics kit made up of LEGO blocks and specialized sensors and a motor that Scratch can natively interact with using motor and sensor blocks (Scratch 1.4) and more blocks (pending support in Scratch 2.0). LEGO Mindstorms NXT An advanced robotics kit made up of LEGO blocks and specialized sensors and motors that can be programmed using a modified version of Scratch known as Enchanting. List blocks A category of code blocks used to store lists of data used by applications when they execute. Local variable Variables that can be modified only by scripts belonging to the sprite in which the variable is defined. Logical error An error resulting from a mistake the programmer makes when developing the logic implemented by a script. Looks blocks Code blocks that affect sprite and background appearance and display text. Loop A collection of one or more code blocks that are repeatedly executed. Not For Sale

4 E-418 Glossary Not For Sale MaKey MaKey Kit An electronic circuit board used to conduct experiments based on the opening and closing of electric circuits. Monitor A small block that displays the value currently assigned to the code block. More blocks A category of code blocks in Scratch 2.0 that allows the creation of custom code blocks. Mosaic A special graphics effect that creates an image made up of repeated instances of a sprite or background. Motion blocks Code blocks that control sprite placement, direction, rotation, and movement. MP3 An audio file that utilizes advanced compression technology while retaining high audio quality. My Stuff A page assigned to every registered Scratch user, in which they can view and manage all their projects and studios. Nest The process of embedding one set of code blocks within another set of code blocks. Operator blocks Code blocks that perform mathematical operations, logical comparisons, rounding, other arithmetic operations, and different string operations. Order of precedence The set of rules that are followed when evaluating a numeric expression. Paint Editor A Scratch program that supports the creation of graphics files to be used as the basis for creating and modifying sprites and backgrounds. Pen A virtualized drawing tool that can be used to draw on the stage. Pen blocks Code blocks that can be used to draw using different colors and pen sizes. PicoBoard A specialized piece of hardware that you attach to your computer to collect and process environmental and user-provided input collected via sensors and button controls. Pixelate A special graphics effect that displays a sprite or background at a lower resolution than the resolution at which it was created. Procedure A script that can be called upon to run by name from other scripts within a sprite, reducing project complexity and size. Program The name used to refer to a Scratch project as it executes. Project A collection of sprites, scripts, backgrounds, and sounds that is used as the basis for creating Scratch applications.

5 Glossary E-419 Profile A page assigned to every registered Scratch user that uniquely identifies the user s username, Scratcher status, and recent activities. Real number A number that includes a decimal number. Remix The process of taking an existing Scratch project and modifying it to create something new. Reporter block A code block that has either rounded or angled sides and is specifically designed as a mechanism for providing input for other code blocks to process. Rotation center The point on a sprite that remains in position when a sprite is rotated. Run-time error An application error that occurs when an application attempts to perform an illegal action. Scope The area within an application where a variable s value can be accessed and modified. Scratch Board See PicoBoard. Scratch cards PDF files that you can print and use as a quick reference for performing certain tasks. Scratcher Someone who has joined the Scratch community. Script A collection of code blocks that outline the programming logic that influences the operation of sprite. Scripts area The area in the Scratch Script Editor where scripts are displayed and configured. Sensing blocks Code blocks that can be used to determine the location of the mouse pointer, its distance from other sprites, and whether a sprite is touching another sprite. Sound An audio file that is played within a Scratch program as s sound effect or background noise. Sound blocks Code blocks that control the playback and volume of musical notes and audio files. Sprite A two-dimensional image drawn on a transparent background, which can be moved around the stage. You can change its appearance using different costumes. Squeak A cross-platform programming language used to develop Scratch. Stack blocks Code blocks with a notch at the top or a bump at the bottom that can be snapped together with other blocks to define a script s programming logic. Stacks Another term for a script. Not For Sale

6 E-420 Glossary Not For Sale Stage The background area on the Scratch IDE upon which sprites are displayed during application execution. String A set of characters that can be displayed within thought and speech bubbles. Studio A web page owned by a Scratch user to organize and store Scratch projects. Tempo A measurement of the speed, in beats per minute, at which a drum or note is played. Troubleshooting The identification, location, and elimination of programming errors, or bugs, that prevents applications from executing properly. Variable A location in memory where an individual piece of data is stored. Variable scope The location within an application that the variable s value can be modified. Variable blocks A category of code blocks whose purpose is to store data used by applications when they execute. Vector A type of graphic in which a graphics image is stored as a collection of rules that tell a vector editor how to construct a graphic. Wave A file with a.wav extension that supports the storage and playback of audio files. Whirl A special graphic effect that twists and distorts a portion of a costume or background.