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GK One-Line Question & Answer

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Computer Fundamentals → Introduction to Computer 38

CI in CI/CD stands for?
Continuous Integration — merging code frequently with automated testing
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CD in CI/CD can mean?
Continuous Delivery or Continuous Deployment
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Jenkins is used for?
CI/CD automation (build, test, deploy pipelines)
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Infrastructure as Code (IaC) tools include?
Terraform, Ansible, CloudFormation
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Immutable infrastructure means?
Servers are never modified after deployment — replaced instead of patched
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Blue-green deployment strategy uses?
Two production environments alternating traffic for zero-downtime deploys
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Canary deployment releases new version to?
Small subset of users first before full rollout
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Feature flags/toggles allow?
Enabling/disabling features at runtime without deploying new code
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A/B testing in software means?
Testing two versions of a feature with different user groups
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Which design pattern defines object creation interface but lets subclasses decide which class to instantiate?
Factory Method
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Observer design pattern is used for?
Event handling and notification (publish-subscribe)
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SOLID principles 'S' stands for?
Single Responsibility Principle
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SOLID 'O' stands for?
Open/Closed Principle
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SOLID 'L' (Liskov Substitution Principle) states?
Objects of derived class must be substitutable for base class objects
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SOLID 'I' (Interface Segregation) states?
Clients should not depend on interfaces they don't use
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SOLID 'D' (Dependency Inversion) states?
High-level modules should not depend on low-level modules — both depend on abstractions
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DRY principle in software means?
Don't Repeat Yourself — avoid code duplication
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KISS principle means?
Keep It Simple, Stupid — avoid unnecessary complexity
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YAGNI principle means?
You Aren't Gonna Need It — don't add functionality until needed
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Which software testing is done without knowledge of source code?
Black box testing
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White box testing requires?
Knowledge of internal code structure and logic
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TDD (Test-Driven Development) workflow is?
Write failing test, write code to pass, refactor
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BDD (Behavior-Driven Development) uses?
Human-readable specifications (Given-When-Then)
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Static code analysis is performed?
Without executing code — analyzes source code directly
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Code coverage measures?
Percentage of code executed during testing
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Mocking in unit testing?
Creates fake objects simulating real dependencies
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Continuous Monitoring in DevOps tracks?
Application performance, errors, and infrastructure health
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APM (Application Performance Monitoring) tools include?
Datadog, New Relic, Dynatrace
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ELK Stack stands for?
Elasticsearch, Logstash, Kibana — for log management
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Prometheus is used for?
Metrics collection and alerting
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Grafana is used to?
Visualize metrics data from Prometheus and other sources
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Chaos engineering intentionally?
Introduces failures to test system resilience
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Service Level Objective (SLO) is?
Internal target for service reliability (e.g., 99.9% uptime)
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Error budget in SRE (Site Reliability Engineering) is?
Allowable unreliability (100% - SLO)
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Which programming paradigm treats computation as evaluation of mathematical functions?
Functional programming
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In floating point, NaN (Not a Number) represents?
Invalid/undefined result (e.g., 0/0, sqrt(-1))
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IEEE 754 positive infinity is represented by?
All exponent bits 1, mantissa all 0, sign 0
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Denormalized (subnormal) numbers in IEEE 754 handle?
Numbers too small for normal representation (near zero)
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Computer Fundamentals → Memory Units 1

GitLab CI/CD differs from Jenkins in?
Built-in CI/CD within GitLab platform (no separate server needed)
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Computer Fundamentals → Number System 1

Which number system is used internally by IPv4 routing tables?
Binary
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