Programmers have to protect their program through defensive designing. Their code has to be well maintained Have to reduce number of bugs/errors Think of all possible ways the user could misuse their program Input Sanitisation is removing any unwanted characters before passing data through the program. Input Validation is checking that the data entered meetsContinue reading “Defensive Designing”
Category Archives: Computing
Flash Storage
Types of flash storage: USB pen drives and memory cards(e.g. SD cards) are also flash-based, solid-state storage. They’re much slower than SSDs and have a much shorter read/write life. They’re used to expand the storage capacity for small devices like cameras, smartphones and tablets (which are way too small for SSDs and HDDs). Their capacityContinue reading “Flash Storage”
Secondary Storage (HDD and SSD)
Secondary Storage: Primary storage: This type of memory is volatile. It refers to the memory areas that the CPU can access very quickly: like CPU registers, cache, ROM and RAM. It also has the fastest read and write speeds. Secondary storage: It is non-volatile memory. It stores data (operating systems, applications and user files) thatContinue reading “Secondary Storage (HDD and SSD)”
Ethical Reasons and Legalisation GCSE Computing OCR:
Computer Misuse Act 1990: Cannot gain unauthorised access on a private network on any user’s computer. Cannot gain unauthorised access on a network on any user’s computer to commit a crime. Cannot MAKE, OBTAIN or SUPPLY malware. Freedom Of Information’s Act 2000: This is where the public can request to view their personal data storedContinue reading “Ethical Reasons and Legalisation GCSE Computing OCR:”
Fetch-Decode-Execute Cycle
The Fetch-Decode-Execute cycle: FETCH: Copy the memory address from the program counter to the MAR. Copy the instruction stored in the MAR address to the MDR. Increment (increase) the program counter to the point to the address of the next instruction, ready for the next cycle. DECODE: The instructions in the MDR is decided byContinue reading “Fetch-Decode-Execute Cycle”
RAM and Virtual Memory GCSE Computing
Ram is high speed, volatile memory: RAM (Radom Access Memory) is used as the main memory in a computer. It can be read or written to. RAM is volatile. Volatile memory is temporary memory. It requires power to retain its data. Non-volatile memory is permanent memory – It keeps its contents even when it hasContinue reading “RAM and Virtual Memory GCSE Computing”