BGCSE Computer Studies 0597 flashcards
BGCSE Computer Studies 0597 · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Von Neumann architecture
- Design where program instructions and data share the same main memory and are fetched over the same bus to the CPU, which processes them one step at a time.
- Cache memory
- Small, fast memory between the CPU and RAM that stores recently used instructions and data, reducing average access time and speeding up processing.
- Solid state drive
- Secondary storage using flash memory chips with no moving parts, giving fast access, quiet operation and low power use, but limited write cycles.
- Operating system
- System software that manages memory, processes, files and devices, provides a user interface, and controls access to hardware resources.
- Compiler versus interpreter
- A compiler translates the entire source program into machine code before running it; an interpreter translates and executes one statement at a time.
- Device driver
- Software that translates general commands from the operating system into signals a specific hardware device can understand and act on.
- Two's complement
- Binary method for signed integers where the leftmost bit gives the sign; negating a value means inverting all bits and adding one.
- Hexadecimal notation
- Base-16 number system using digits 0-9 and A-F, where each digit represents four binary bits, giving compact representation of byte values.
- Bitmap file size
- Calculated as width in pixels times height in pixels times colour depth in bits, divided by eight for bytes, before any compression is applied.
- Character encoding standards
- ASCII maps 128 characters to 7-bit codes; Unicode uses variable-length codes to represent characters from all writing systems worldwide.
- LAN versus WAN
- A local area network covers a single site under one owner; a wide area network spans large distances, usually using links hired from telecom providers.
- Star topology
- Network layout with every device cabled to a central switch or hub; a broken cable affects one device, but central device failure stops the network.
- TCP and UDP
- TCP is connection-oriented, acknowledges packets and retransmits losses; UDP is connectionless, sending packets without guaranteeing delivery or order.
- Domain name system
- Distributed naming service that translates human-readable domain names into numeric IP addresses so devices can route requests to the correct server.
- Packet switching
- Method where messages are split into packets, each routed independently by the best available path and reassembled at the destination in sequence order.
- Cloud computing
- Provision of storage, processing or software as a service over a network, with data held on remote servers accessed from any connected device.
- Internet of Things
- Network of everyday objects fitted with sensors, software and connectivity that collect and exchange data without direct human intervention.
- Search engine indexing
- Process where crawler-collected web pages are analysed and stored in a database of keywords, so queries can return ranked matching results.
- Blockchain ledger
- Distributed append-only record of transactions grouped into blocks, each block containing a hash of the previous one to resist alteration.
- Primary and foreign keys
- A primary key uniquely identifies each record in a table; a foreign key is a primary key stored in another table to link related records.
- Validation versus verification
- Validation checks that entered data is reasonable and within rules; verification confirms the data was copied or captured accurately from source.
- Relational database
- Collection of related tables linked by shared key fields, allowing data to be stored once and combined through queries rather than duplicated.
- Data redundancy
- Storing the same data in more than one place, which wastes storage and risks inconsistency when only one copy is updated.
- Syntax versus logic error
- A syntax error breaks the rules of the language and stops translation; a logic error lets the program run but produce incorrect results.
- Count-controlled loop
- Iteration that repeats a fixed number of times, controlled by a counter with a start value, end value and increment set before entry.
- Binary search
- Search that repeatedly halves a sorted list, comparing the middle item to the target, and is far faster than linear search on large data.
- Trace table
- Table used in a dry run to record each variable's value after every step of an algorithm, revealing logic errors and unexpected results.
- Parallel running
- Changeover method where old and new systems run together on the same data until results agree, giving fallback but doubling workload.
- Data flow diagram
- Diagram showing processes, external entities, data stores and the flows of data between them, modelling what a system does rather than how.
- Feasibility study
- Assessment of whether a proposed system is technically possible, economically worthwhile, legally acceptable and operationally workable before development begins.
- Phishing
- Deceptive emails or messages imitating trusted organisations to trick users into revealing passwords, card numbers or other confidential details.
- Digital divide
- Gap between people who have affordable access, devices and skills to use ICT effectively and those who are excluded from its benefits.