"Scratch" - what is it, definition of the term
Scratch is a block‑based visual programming environment that enables users, particularly beginners, to create interactive projects—animations, games, simulations—by assembling color‑coded command blocks, thereby removing the requirement for textual code and delivering immediate visual feedback.
Detailed information
The visual programming environment created by the MIT Media Lab enables users to construct interactive stories, games, and simulations by dragging and connecting colored code blocks. Its interface consists of a stage area that displays the output, a sprite pane for managing characters, and a block palette organized into motion, looks, sound, events, control, sensing, operators, and variables. Each block represents a specific command; stacking them defines the sequence of actions for a sprite.
The system supports multiple input methods, including keyboard, mouse, and external devices such as microcontrollers. Extensions provide direct access to sensors, enabling projects that react to real‑world data. For example, a user can program a virtual rat to navigate a maze by processing distance readings from an ultrasonic sensor attached to a physical prototype.
Educational use focuses on developing computational thinking without requiring textual syntax. Lessons typically progress from simple motion commands to conditionals and loops, then to data handling with lists and custom blocks. Assessment criteria emphasize problem decomposition, algorithmic design, and iterative testing.
Key features include:
- Sprite library: pre‑designed characters and the ability to import custom images.
- Costume and sound editing: tools for creating visual and auditory assets directly within the platform.
- Community sharing: a cloud‑based repository where projects can be uploaded, remixed, and commented on by other users.
- Version control: automatic saving of project states, allowing rollback to previous versions.
- Hardware integration: support for robotics kits and microcontroller boards, facilitating real‑time interaction between code and physical devices.
When modeling rodent behavior, users often employ the sensing category to detect collisions with maze walls, then apply conditional blocks to change direction. Variables store the number of steps taken, while lists record visited locations, enabling the creation of algorithms that mimic foraging patterns observed in laboratory rats and mice.
The platform runs in modern web browsers and offers offline desktop versions for Windows, macOS, and Linux. System requirements are minimal, making it accessible on low‑spec hardware commonly found in school computer labs.