1.3

• What is asymmetric encryption?


  An encryption technique where a public key is used to encrypt data and a private key is used to decrypt it.
• How does asymmetric encryption ensure security?

  It uses a public key for encryption and a private key for decryption, ensuring only the recipient can decrypt the data.
• What is dictionary coding?

  A type of lossless compression where text is matched with entries in a dictionary and substituted with unique codes.
• What is the purpose of hashing?

  To transform data into a hash value for validating credentials without revealing the original data.
• What is lossless compression?

  A compression algorithm that retains all data in the file without losing any information.
• How does lossy compression differ from lossless compression?

  Lossy compression removes non-essential data, leading to a decrease in accuracy, while lossless retains all data.
• What is run-length encoding?

  A type of lossless compression that stores repeated data occurrences as single values with their counts.
• What is symmetric encryption?

  An encryption technique that uses the same key for both encryption and decryption.
• What does atomicity mean in database transactions?

  All transactions should either succeed or fail, never partially processed.
• Why is consistency important in database transactions?

  Each transaction must obey defined validation rules to maintain referential integrity.
• What does durability mean in the context of database transactions?

  Once a transaction has begun, it must be completed under all circumstances.
• What is entity-relationship modeling?

  A method of visually describing data tables and their relationships to reduce redundancy in a relational database.
• What is first normal form (1NF) in databases?

  A table with no repeating attributes where each record and attribute intersection produces exactly one value.
• What is a flat file database?

  A database that uses a single table data structure to store all data.
• What is a foreign key in a relational database?

  A linking attribute that joins two tables by being a primary key in one and a foreign key in the other.
• What is indexing in databases?

  The process of creating an index of primary keys to retrieve records based on their primary key location.
• What does isolation mean in database transactions?

  No transaction should overwrite other transactions that are occurring simultaneously.
• What is normalization in databases?

  The formal process of optimally designing data tables by reducing redundancy and repetition.
• What is a primary key?


  A unique identifier that identifies each record in a table.
• What is record locking in databases?

  A technique used to prevent simultaneous access to data by locking a record during editing or updating.
• What is redundancy in databases?


  The unnecessary repetition of a field in multiple tables.
• What is referential integrity?

  The idea of keeping a database consistent by ensuring changes are accounted for in all linked tables.
• What are relational databases?

  A database where separate tables are made for each entity, with relationships represented by foreign keys.
• What is a secondary key?

  A key that can be used as an alternative index to access or sort records in a table.
• What is second normal form (2NF)?

  A table in 1NF that has repeating data removed and put into a new table with appropriate relationships.
• What is third normal form (3NF)?

  A table in 2NF where all attributes not the primary key are fully dependent on the primary key.
• What is transaction processing?


  The idea of ensuring that any change in the state of a database conforms to ACID rules.
• What is circuit switching?

  A method for sending data by creating a dedicated communication channel between two nodes.
• What is a client-server network?

  A type of network where clients connect to one or more central servers that handle service requests.
• What is the Domain Name System (DNS)?

  A hierarchical naming system that maps domain names to IP addresses.
• What is encryption?

  The process of converting original data into a form that cannot be understood by unauthorized users.
• What are firewalls used for?

  To monitor network traffic and prevent unauthorized access between networks.
• What are Local Area Networks (LANs)?

  A network connecting a group of computing devices in a single geographical area.
• What is packet switching?


  A method for sending data by breaking it into packets that are sent independently and reassembled at the destination.
• What is a peer-to-peer network?

  A type of network where computers are connected to each other and share resources without a central server.
• What is protocol layering?

  A technique that divides a complex system into functional layers and assigns protocols for each layer.
• What are proxies in networking?

  A server application that intercepts data packets to hide true network addresses and restrict access.
• What is the Transmission Control Protocol / Internet Protocol (TCP/IP) stack?

  A suite of networking protocols that allow networked computers to communicate through connected layers.
• What are Wide Area Networks (WANs)?

  A network connecting computing devices over a large geographical area, typically using third-party carriers.
• What are Cascading Style Sheets (CSS)?


  A style language used to define the layout and design of a webpage.