Grade 9 Coding and Robotics November Exam Study Notes

Comprehensive vocabulary flashcards covering the core concepts, software commands, spreadsheet functions, programming terminology, CAD modeling tools, and robotic hardware protocols specified in the Grade 9 Coding and Robotics curriculum.

HTML

A markup language describing the structure and content of a web page using tags that tell the browser what content is.

DOCTYPE

A directive at the start of an HTML document that instructs the browser to interpret the page as HTML5; it is a directive, not a tag.

An HTML element containing metadata and the page title; it does not contain visible page content.

An HTML tag inside the head element that specifies the text shown on the browser tab.

The HTML element containing visible content such as text, images, lists, links, and tables.

CSS (Cascading Style Sheets)

A styling language used alongside HTML that controls how elements look and separates page content from design.

Inline CSS

A CSS method written inside an individual HTML tag using the style attribute (style="…"); it affects only that tag and is not preferred.

Internal CSS

A CSS method written inside a

External CSS

A CSS method where rules are stored in a separate .css file linked in the ; preferred because one file can style multiple pages.

CSS Class Selector

A reusable selector identified by a preceding dot (.), applied to HTML elements with the class attribute.

CSS ID Selector

A unique selector identified by a preceding hash symbol (#), applied to a single HTML element with the id attribute once per page.

Workbook

The saved Excel file, which can contain multiple worksheets.

Range

A designated group of cells in a spreadsheet, written as start and end addresses separated by a colon (e.g., B3:B10).

Formula (Excel)

A custom calculation written by the user that begins with an equals sign (=), such as =B3*C3.

Function (Excel)

A predefined, built-in spreadsheet calculation, such as =SUM(B3:B10).

Fill Handle

The small black plus icon on the corner of a selected cell used to copy data or extend a series.

Sort (Excel)

A tool that reorders rows based on criteria; requires selecting all related columns and preserving table headers.

Filter (Excel)

A tool that temporarily hides non-matching rows from view without deleting the underlying data.

Conditional Formatting

A spreadsheet feature that automatically alters the visual appearance of cells when their values satisfy a specified rule.

Error

An Excel cell display indicating that a number or date exceeds the column width; resolved by widening the column or using AutoFit.

COUNT

A spreadsheet function that tallies only cells containing numeric values.

COUNTA

A spreadsheet function that tallies all non-empty cells, including both numbers and text.

COUNTBLANK

A spreadsheet function that counts the total number of empty cells in a specified range.

SUMIF

A spreadsheet function that adds the values in a specified range that meet a given condition.

Relative Cell Reference

A cell reference without locks (e.g., B3) where both the column and row adjust automatically when copied.

Absolute Cell Reference

A cell reference locked with dollar signs (e.g., B$1) so that both the column and row stay fixed when copied.

Mixed Cell Reference

A cell reference containing a single lock symbol (e.g., $B3$ or B$1) that fixes either only the column or only the row when copied.

Computational Thinking

A structured problem-solving approach consisting of breaking down tasks, recognizing patterns, omitting irrelevant details, and defining precise algorithms.

Decomposition

The pillar of computational thinking focused on breaking a complex problem down into smaller, manageable parts.

Pattern Recognition

The pillar of computational thinking focused on identifying repetition, trends, or shared characteristics across problems.

Abstraction

The pillar of computational thinking focused on retaining important information while filtering out irrelevant details.

Algorithm

A defined set of clear, step-by-step ordered instructions designed to solve a problem or complete a task.

IPO Model

A fundamental processing sequence consisting of Input (information needed), Process (actions or calculations performed), and Output (result produced).

Flowchart Diamond

A standardized flowchart symbol used to represent a decision point with branching Yes/No paths.

Flowchart Parallelogram

A standardized flowchart symbol used to denote input or output operations.

Flowchart Rectangle

A standardized flowchart symbol representing a process, calculation, or action.

Flowchart Oval / Rounded Rectangle

A standardized flowchart terminal symbol marking the start or end of a procedure.

Pseudocode

A generic, human-readable plain language representation of an algorithm written before actual programming, using terms like BEGIN, INPUT, DISPLAY, and the left-arrow symbol (←) for assignment.

IDE (Integrated Development Environment)

A comprehensive software application providing facilities for computer programming; jGRASP is the IDE used in this course.

Bytecode

The intermediate representation of compiled Java source code (.class file) that can be executed on any device featuring a Java Virtual Machine.

Java Virtual Machine (JVM)

The execution environment that executes compiled Java bytecode, conferring cross-platform portability.

Compile

The process of verifying program syntax and translating Java source code (.java) into executable bytecode (.class).

Class (Java)

A blueprint or recipe defining the fields and methods that characterise an entity.

Object (Java)

A specific software instance instantiated from a class template using the new keyword.

Method (Java)

A named block of code within a class that performs a specific action or operation.

Variable (Java)

A named storage memory location assigned a specific data type to hold a changeable value.

Syntax

The strict set of grammatical rules and structural conventions governing valid statements in a programming language.

Main Method

The mandatory program entry point for Java applications, defined as public static void main(String[] args).

Workbench (FreeCAD)

A specialized collection of tools grouped together for a specific 3D CAD modeling task, such as Sketcher or Part Design.

Body (FreeCAD)

The organizational container in FreeCAD that holds all features and operations of a single continuous 3D part.

Sketch (FreeCAD)

A planar 2D technical drawing that serves as the base profile for generating 3D solid geometry.

Construction Line

A blue guide line in FreeCAD used for establishing measurements and geometric alignment that does not form part of the final 3D solid.

Pad (FreeCAD)

A tool that extrudes a 2D sketch by adding solid material to form a 3D feature.

Pocket (FreeCAD)

A tool that cuts away material from an existing 3D solid using a 2D profile to make a hole or recess.

Fillet (FreeCAD)

A feature that rounds off a sharp exterior edge or interior corner of a 3D model according to a specified radius.

Datum Plane

An independent artificial reference surface created in FreeCAD to facilitate sketching from a specific position or angle.

Degree of Freedom (DOF)

An independent direction or dimension in which unconstrained 2D sketch geometry can move, stretch, or rotate.

Fully Constrained Sketch

A sketch where every geometric parameter is completely defined, having zero degrees of freedom (0 DOF) and indicated by green lines.

Seed Feature

The original 3D feature (such as a single Pad or Pocket) chosen to be replicated by a pattern tool.

Linear Pattern

A FreeCAD modeling tool that duplicates a selected seed feature repeatedly along a specified straight line.

Polar Pattern

A FreeCAD modeling tool that repeats a seed feature radially around a central rotational axis.

Revolve (FreeCAD)

A tool that sweeps a closed 2D profile around a defined rotational axis located completely to one side of the profile to generate a 3D solid.

Voltage ($V$)

The electrical potential difference or pressure driving charges through a circuit; quantified in volts ($\text{V}$).

Current ($I$)

The rate of electrical charge flow through a conductor; measured in amperes ($\text{A}$) or milliamperes ($\text{mA}$).

Resistance ($R$)

The opposition offered by a material or component to the passage of electric current; measured in ohms ($\Omega$).

Pull-Down Resistor

A resistor (commonly $10\,\text{k}\Omega$) connected between an input pin and ground to prevent floating by keeping the logic state at LOW ($0\,\text{V}$) when an input switch is open.

Actuator

An output component in a robotics system (such as a motor or buzzer) that converts electrical signals into physical action.

Sensor

An input device in a robotic system (such as an LDR or ultrasonic sensor) that detects physical conditions and converts them into electrical signals.

Continuous Servo

A modified servo motor capable of full rotation where speed and direction are determined by input values ($0$ = full reverse, $90$ = stop, $180$ = full forward).

Positional Servo

A servo motor that moves precisely to a target angular position between $0^\circ$ and $180^\circ$ and maintains that position.

L293D

An integrated H-bridge motor driver chip designed to control the rotation direction and speed of two DC motors while shielding the microcontroller from excessive current draw.

I2C

A synchronous serial communication protocol utilizing two shared signal lines—SDA (data) and SCL (clock)—to connect up to 127 individually addressed devices.

UART

An asynchronous point-to-point serial communication protocol that relies on two dedicated wires: transmit (TX) and receive (RX).

SPI

A high-speed synchronous serial communication protocol that achieves fast data transfer rates using multiple dedicated wires and pins.