Tech+ flashcards
Tech+ · 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.
- Bit
- A bit is a single binary digit, either 0 or 1, and it is the smallest unit of digital data; eight bits grouped together form one byte.
- Byte
- A byte is a group of eight bits and is the standard unit for measuring storage; one byte can represent 256 distinct values or one ASCII character.
- Hexadecimal
- Hexadecimal is a base-16 number system using digits 0-9 and letters A-F; one hex digit represents exactly four binary bits, so two hex digits equal one byte.
- Bandwidth versus throughput
- Bandwidth is the maximum data capacity of a connection, while throughput is the actual measured rate of successful data transfer, which is typically lower due to overhead and congestion.
- Latency
- Latency is the delay between sending a request and receiving a response, usually measured in milliseconds; lower latency improves responsiveness for real-time applications such as video calls.
- Cloud computing characteristics
- Cloud computing delivers computing resources over a network with on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured or metered service billing.
- RAID 5
- RAID 5 stripes data across at least three disks with distributed parity, allowing the array to survive one disk failure while sacrificing the capacity of one drive.
- Private IPv4 ranges
- Private IPv4 ranges are 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16; they are not routable on the public internet and require NAT to reach external networks.
- APIPA address
- An APIPA address in the 169.254.0.0/16 range is self-assigned by a host when no DHCP server responds, indicating the host can reach only its local link.
- SSD versus HDD
- A solid-state drive uses flash memory with no moving parts for fast random access, while a hard disk drive uses spinning platters and offers lower cost per gigabyte.
- HTTPS default port
- Port 443 is the default TCP port for HTTPS, carrying HTTP traffic encrypted with TLS; port 80 serves unencrypted HTTP.
- Type 1 hypervisor
- A Type 1 hypervisor, also called bare-metal, runs directly on the host hardware and manages guest virtual machines itself, offering better performance and security than a hosted Type 2 hypervisor.
- Operating system role
- An operating system manages hardware, schedules processes, allocates memory, provides a file system, and presents a user interface so application software can run on the device.
- Subscription licensing
- Subscription licensing charges recurring fees for continued use of software, typically including updates and support, unlike a perpetual license that is bought once.
- Container versus virtual machine
- Containers share the host operating system kernel and package only the application and its dependencies, while virtual machines each include a full guest operating system, making containers lighter.
- Productivity software
- Productivity software such as word processors, spreadsheets, and presentation tools helps users create, edit, and organize documents and data for everyday business tasks.
- Software patch
- A patch is a small software update that fixes bugs or closes security vulnerabilities in an installed application, while an upgrade moves to a newer major version with added features.
- SDLC phases
- The software development life cycle typically moves through planning, analysis, design, implementation, testing, deployment, and maintenance, with each phase producing artifacts that feed the next.
- Waterfall versus Agile
- Waterfall completes each phase sequentially with fixed requirements, while Agile delivers working software in short iterative increments and welcomes changing requirements through continuous feedback.
- Version control system
- A version control system such as Git records changes to source files over time, letting developers branch, compare, merge, and revert work without overwriting each other's contributions.
- Unit testing
- Unit testing verifies individual functions or components in isolation, usually written by developers and run automatically, to catch defects early before integration and system testing.
- REST API methods
- REST APIs use HTTP verbs: GET retrieves data, POST creates a resource, PUT or PATCH updates it, and DELETE removes it, with payloads usually formatted as JSON.
- Primary key
- A primary key is a column or set of columns that uniquely identifies each row in a table and cannot contain null values or duplicate entries.
- Foreign key
- A foreign key is a column that references the primary key of another table, enforcing referential integrity so child rows cannot point to nonexistent parent records.
- Differential backup
- A differential backup copies all data changed since the last full backup and grows larger each day until the next full backup, whereas an incremental backup captures only changes since the last backup of any type.
- ACID properties
- ACID describes transaction guarantees: atomicity means all-or-nothing, consistency preserves valid data states, isolation prevents interference between concurrent transactions, and durability keeps committed data after failure.
- SQL SELECT statement
- The SELECT statement retrieves rows from one or more tables; WHERE filters rows, JOIN combines tables on related keys, and GROUP BY aggregates rows for summary calculations.
- CIA triad
- The CIA triad describes three security goals: confidentiality keeps data secret from unauthorized parties, integrity keeps data accurate and unaltered, and availability keeps systems accessible to authorized users.
- Multi-factor authentication
- Multi-factor authentication requires two or more independent credential types from knowledge, possession, and inherence categories, so a stolen password alone is not enough to gain access.
- Symmetric encryption
- Symmetric encryption uses a single shared key for both encryption and decryption, as in AES; it is fast but requires secure key distribution to every party involved.
- Worm versus virus
- A virus attaches to a host file and needs user action to spread, while a worm self-replicates across networks without a host program or user interaction.
- Principle of least privilege
- The principle of least privilege grants users and processes only the access rights required for their tasks, limiting the damage that a compromised account or malicious insider can cause.