Teacher License – Computer Complete Review Guide 2026–2027

4. A compiler translates the whole program before running it and reports syntax errors together; an interpreter executes line by line and stops at the first error.
5. Procedural programming splits a program into procedures (functions) run in sequence; object-oriented programming bundles data (attributes) and behavior (methods) into objects created from classes (6.10.5.2).
6. OOP pillars: encapsulation (hiding data inside the class), inheritance (a subclass inherits from a parent class), polymorphism (one name, different behavior), abstraction (showing only what is essential).
7. A class is a blueprint and an object is an instance of it. The constructor runs when the object is created: it is named __init__ in Python and has the class name in Java and C++.
8. In Python indentation defines blocks; in Java and C++ braces { } do, and most statements end with a semicolon.
9. Arrays and lists are indexed from 0 and reading an element by index is fast (O(1)). For a = [4, 7, 9], a[0] is 4, a[2] is 9 and len(a) is 3.
10. A stack is LIFO with push, pop and peek, and is used for undo, function calls and expression evaluation. A queue is FIFO with enqueue and dequeue, and is used for print queues and task scheduling (6.10.5.3).
11. A tree has one root, each node except the root has one parent, and a node with no children is a leaf. In a binary tree each node has at most two children. In a binary search tree the left child is smaller than the parent and the right child is larger.
12. Binary tree traversals: preorder (root, left, right), inorder (left, root, right), postorder (left, right, root). An inorder traversal of a binary search tree gives the values in ascending order.
13. Linear search checks elements one by one (O(n)) and needs no ordering; binary search halves a sorted range at each step (O(log n)). Bubble sort compares neighbours and swaps them (O(n²)).
14. Mobile apps are native (Kotlin or Java for Android, Swift for iOS) or cross-platform (such as Flutter and React Native). MIT App Inventor is a block-based tool suited to beginners. An app has screens, components, events (such as a button press) and code that handles each event, and is tested on an emulator or a real device (6.10.5.4).
15. AI makes machines perform tasks that need human intelligence. Machine learning learns patterns from data instead of hand-written rules, and deep learning uses multi-layer neural networks. Applications include speech recognition, computer vision, natural language processing and recommendation systems (6.10.5.5).
16. Types of machine learning: supervised learns from labeled data (classification, prediction), unsupervised finds patterns in unlabeled data (such as clustering), and reinforcement learns from rewards and penalties through trial.
17. A robot has sensors (camera, distance, touch), a controller or processor, and actuators (motors). It works in a loop: read the sensor, decide in the program, then act. Types include industrial arms, mobile robots, humanoids and drones (6.10.5.6).
18. Microcontrollers such as Arduino and micro:bit are used for digital control: they read inputs from digital or analog pins and drive outputs such as an LED or a motor. A digital pin has only two values: 0 and 1.

Common mistakes in this chapter

• ✕ Mixing up = (assignment) and == (comparison): if x = 5 is an error in Python and Java; the correct test is if x == 5.
• ✕ Integer division: 7/2 is 3 in Java and C++ when both operands are int, but 3.5 in Python 3. In Python 7//2 is 3 and 7%2 is 1.
• ✕ The end of range in Python is excluded: range(1, 5) gives 1, 2, 3, 4 only, and range(5) runs from 0 to 4.
• ✕ Confusing stack and queue: the last item pushed on a stack is the first out; in a queue the first item in is the first out.
• ✕ Overloading is the same method name with different parameters in one class; overriding is a subclass redefining a parent method with the same signature.
• ✕ Using binary search on unsorted data: it only works correctly once the data is sorted.
• ✕ AI is broader than machine learning, and machine learning is broader than deep learning. An option that reverses this nesting is wrong.
• ✕ A sensor brings data from the environment into the robot; an actuator (such as a motor) carries out the movement. Do not swap them.