Computer Science 0478 — specification explorer

1. Number systems

• 1.1.1Understand how and why computers use binary to represent all forms of data
  4 resources
• 1.1.2

  (a) Understand the denary, binary and hexadecimal number systems (ii) positive denary and positive hexadecimal (iii) positive hexadecimal and positive binary:

  • (b) Convert between
  • (i) positive denary and positive binary
  5 resources
• 1.1.3Understand how and why hexadecimal is used as a beneficial method of data representation
  4 resources
• 1.1.4

  (a) Add two positive 8-bit binary integers it occurs in binary addition:

  • (b) Understand the concept of overflow and why
  1 resource
• 1.1.5Perform a logical binary shift on a positive 8-bit binary integer and understand the effect this has on the positive binary integer
  4 resources
• 1.1.6Use two’s complement to represent positive and negative 8-bit binary integers
  4 resources

2. Text, sound and images

• 1.2.1Understand how and why a computer represents text and the use of character sets, including American standard code for information interchange (ASCII) and Unicode
  3 resources
• 1.2.2Understand how and why a computer represents sound, including the effects of the sample rate and sample resolution
  3 resources
• 1.2.3Understand how and why a computer represents an image, including the effects of the resolution and colour depth
  3 resources

3. Data storage and compression

• 1.3.1Understand how data storage is measured
  3 resources
• 1.3.2Calculate the file size of an image file and a sound file, using information given
  3 resources
• 1.3.3Understand the purpose of and need for data compression
  3 resources
• 1.3.4Understand how files are compressed using lossy and lossless compression methods
  3 resources

1. Types and methods of data transmission

• 2.1.1

  (a) Understand that data is broken down into packets to be transmitted:

  • (b) Describe the structure of a packet
  • (c) Describe the process of packet switching
• 2.1.2

  (a) Describe how data is transmitted from one device to another using different methods of data transmission transmission, for a given scenario:

  • (b) Explain the suitability of each method of data
  2 resources
• 2.1.3Understand the universal serial bus (USB) interface and explain how it is used to transmit data
  3 resources

2. Methods of error detection

• 2.2.1Understand the need to check for errors after data transmission and how these errors can occur
  3 resources
• 2.2.2Describe the processes involved in each of the following error detection methods for detecting errors in data after transmission: parity check (odd and even), checksum and echo check
  3 resources
• 2.2.3Describe how a check digit is used to detect errors in data entry and identify examples of when a check digit is used, including international standard book numbers (ISBN) and bar codes
  3 resources
• 2.2.4Describe how an automatic repeat query (ARQ) can be used to establish that data is received without error
  3 resources

3. Encryption

• 2.3.1Understand the need for and purpose of encryption when transmitting data
  4 resources
• 2.3.2Understand how data is encrypted using symmetric and asymmetric encryption
  3 resources

1. Computer architecture

• 3.1.1

  (a) Understand the role of the central processing unit (CPU) in a computer microprocessor:

  • (b) Understand what is meant by a
• 3.1.2

  (a) Understand the purpose of the components in a CPU, in a computer that has a Von Neumann architecture fetch–decode–execute (FDE) cycle including the role of each component in the process:

  • (b) Describe the process of the
  2 resources
• 3.1.3Understand what is meant by a core, cache and clock in a CPU and explain how they can affect the performance of a CPU
  3 resources
• 3.1.4Understand the purpose and use of an instruction set for a CPU
  3 resources
• 3.1.5Describe the purpose and characteristics of an embedded system and identify devices in which they are commonly used
  4 resources

2. Input and output devices

• 3.2.1Understand what is meant by an input device and why it is required
  3 resources
• 3.2.2Understand what is meant by an output device and why it is required
  3 resources
• 3.2.3

  (a) Understand what is meant by a sensor and the purposes of sensors sensor and understand when each sensor would be used, including selecting the most suitable sensor for a given context:

  • (b) Identify the type of data captured by each
  3 resources

3. Data storage

• 3.3.1Understand what is meant by primary storage
  3 resources
• 3.3.2Understand what is meant by secondary storage
  4 resources
• 3.3.3Describe the operation of magnetic, optical and solid-state (flash memory) storage and give examples of each
  3 resources
• 3.3.4Describe what is meant by virtual memory, how it is created and used and why it is necessary
  3 resources
• 3.3.5Understand what is meant by cloud storage
  3 resources
• 3.3.6Explain the advantages and disadvantages of storing data on the cloud in comparison to storing it locally
  2 resources

4. Network hardware

• 3.4.1Understand that a computer needs a network interface card (NIC) to access a network
  3 resources
• 3.4.2Understand what is meant by and the purpose of a media access control (MAC) address, including its structure
  3 resources
• 3.4.3

  (a) Understand what is meant by and the purpose of an internet protocol (IP) address IP address:

  • (b) Understand that there are different types of
  3 resources
• 3.4.4Describe the role of a router in a network
  3 resources

1. Types of software and interrupts

• 4.1.1Describe the difference between system software and application software and provide examples of each
  3 resources
• 4.1.2Describe the role and basic functions of an operating system
  3 resources
• 4.1.3Understand how hardware, firmware and an operating system are required to run applications software
  3 resources
• 4.1.4Describe the role and operation of interrupts
  3 resources

2. Types of programming language, translators and integrated development environments (IDEs)

• 4.2.1Explain what is meant by a high-level language and a low-level language, including the advantages and disadvantages of each
  3 resources
• 4.2.2Understand that assembly language is a form of low-level language that uses mnemonics, and that an assembler is needed to translate an assembly language program into machine code
  2 resources
• 4.2.3Describe the operation of a compiler and an interpreter, including how high-level language is translated by each and how errors are reported
  2 resources
• 4.2.4Explain the advantages and disadvantages of a compiler and an interpreter
• 4.2.5Explain the role of an IDE in writing program code and the common functions IDEs provide
  3 resources

1. The internet and the world wide web

• 5.1.1Understand the difference between the internet and the world wide web
  3 resources
• 5.1.2Understand what is meant by a uniform resource locator (URL)
  3 resources
• 5.1.3Describe the purpose and operation of hypertext transfer protocol (HTTP) and hypertext transfer protocol secure (HTTPS)
  3 resources
• 5.1.4Explain the purpose and functions of a web browser
  3 resources
• 5.1.5Describe how web pages are located, retrieved and displayed on a device when a user enters a URL
  3 resources
• 5.1.6Explain what is meant by cookies and how they are used, including session cookies and persistent cookies
  2 resources

2. Digital currency

• 5.2.1Understand the concept of a digital currency and how digital currencies are used
  3 resources
• 5.2.2Understand the process of blockchain and how it is used to track digital currency transactions
  3 resources

3. Cyber security

• 5.3.1Describe the processes involved in, and the aim of carrying out, a range of cyber security threats
  3 resources
• 5.3.2Explain how a range of solutions are used to help keep data safe from security threats
  3 resources

1. Automated systems

• 6.1.1Describe how sensors, microprocessors and actuators can be used in collaboration to create automated systems
  3 resources
• 6.1.2Describe the advantages and disadvantages of an automated system used for a given scenario
  3 resources

2. Robotics

• 6.2.1Understand what is meant by robotics
  2 resources
• 6.2.2Describe the characteristics of a robot
  3 resources
• 6.2.3Understand the roles that robots can perform and describe the advantages and disadvantages of their use
  3 resources

3. Artificial intelligence

• 6.3.1Understand what is meant by artificial intelligence (AI)
  2 resources
• 6.3.1astandard flowchart symbols that must be used by students when drawing flowcharts
• 6.3.2Describe the main characteristics of AI as the collection of data and the rules for using that data, the ability to reason, and can include the ability to learn and adapt
  4 resources
• 6.3.2alogic gate symbols that must be used by students when drawing logic circuits
• 6.3.3Explain the basic operation and components of AI systems to simulate intelligent behaviour
  3 resources
• 6.3.3aformat in which pseudocode will appear in examinations.
• 6.3.4Students are advised to program solutions to a variety of different problems on a computer, using one of these high-level programming languages: Python, VB.NET or Java.
  4 resources
• 6.3.4aUnderstand standard methods of solution
  5 resources
• 6.3.5

  (a) Understand the need for validation checks to be made on input data and the different types of validation check to be made on input data and the different types of verification check:

  • (b) Understand the need for verification checks
  4 resources
• 6.3.6Suggest and apply suitable test data
  4 resources
• 6.3.7Complete a trace table to document a dry-run of an algorithm
  4 resources
• 6.3.8Identify errors in given algorithms and suggest ways of correcting these errors
  3 resources
• 6.3.9Write and amend algorithms for given problems or scenarios, using: pseudocode, program code and flowcharts
  3 resources

1. Programming concepts

• 8.1.1Declare and use variables and constants
  6 resources
• 8.1.1a

  (f) Understand and use arithmetic, logical and Boolean operators 5 Understand and use nested statements 6 (a) Understand what is meant by procedures, functions and parameters with or without parameters 7 Understand and use library routines:

  • (b) Define and use procedures and functions,
  • (c) Understand and use local and global variables
• 8.1.2Understand and use the basic data types
  5 resources
• 8.1.3Understand and use input and output
  2 resources
• 8.1.4

  (a) Understand and use the concept of sequence (d) Understand and use the concepts of totalling and counting handling:

  • (b) Understand and use the concept of selection
  • (c) Understand and use the concept of iteration
  • (e) Understand and use the concept of string
  8 resources
• 8.1.8Understand how to create a maintainable program
  3 resources

2. Arrays

• 8.2.1Declare and use one-dimensional (1D) and two-dimensional (2D) arrays
  1 resource
• 8.2.2Understand the use of arrays
  2 resources
• 8.2.3Write values into and read values from an array using iteration
  1 resource

3. File handling

• 8.3.1Understand the purpose of storing data in a file to be used by a program
  1 resource
• 8.3.2Open, close and use a file for reading and writing
  2 resources