Information Technology Study Notes: Software Development

Definition: The process of designing, coding, testing, and maintaining software applications.
Key Models:
- Waterfall: Sequential design process; each phase must be completed before the next begins.
- Agile: Iterative approach; promotes flexible responses to change and collaboration.
- DevOps: Integrates development and operations to improve deployment frequency and service reliability.
Programming Languages: Common languages include Java, Python, C#, and JavaScript.
Development Methodologies:
- Scrum: Agile framework for managing complex projects with iterative progress.
- Extreme Programming (XP): Emphasizes technical excellence and frequent releases.
Version Control: Tools like Git are used for tracking changes in software code.

Definition: The systematic organization and management of data in databases.
Key Components:
- DBMS (Database Management System): Software that interacts with end-users, applications, and the database.
- Data Models: Structures for organizing data (e.g., relational, NoSQL).
Normalization: Process of organizing data to reduce redundancy and improve integrity.
SQL (Structured Query Language): Standard language for managing and manipulating relational databases.
Backup and Recovery: Strategies to prevent data loss; includes regular backups and disaster recovery planning.

Definition: Delivery of computing services over the internet, allowing on-demand access to resources.
Service Models:
- IaaS (Infrastructure as a Service): Provides virtualized computing resources over the internet (e.g., AWS EC2).
- PaaS (Platform as a Service): Offers hardware and software tools over the internet (e.g., Google App Engine).
- SaaS (Software as a Service): Delivers software applications over the internet (e.g., Microsoft Office 365).
Deployment Models:
- Public Cloud: Services offered over the public internet, available to anyone.
- Private Cloud: Exclusive use by a single organization, can be managed internally or by third parties.
- Hybrid Cloud: Combination of public and private clouds, allowing data and applications to be shared.
Benefits:
- Scalability: Resources can be adjusted based on demand.
- Cost Efficiency: Reduces the need for on-site hardware and maintenance.
- Accessibility: Services can be accessed from anywhere with internet connectivity.

Process involves designing, coding, testing, and maintaining software applications.
Waterfall Model: Features a linear progression where each phase must be completed before the next starts.
Agile Model: Focuses on iterative development, promoting flexibility and collaboration among team members.
DevOps: Combines development and operations to enhance deployment speed and reliability of services.
Common programming languages include Java, Python, C#, and JavaScript.
Scrum: An Agile framework that manages complex projects by incorporating iterative progress and sprints.
Extreme Programming (XP): Prioritizes technical excellence and encourages frequent software releases.
Version Control: Systems like Git are essential for tracking changes in code over time.

Involves the systematic organization and handling of data within databases.
DBMS (Database Management System): Software facilitating interaction between users, applications, and databases.
Data Models: Frameworks for data organization, including relational and NoSQL models.
Normalization: A method aimed at reducing data redundancy and enhancing data integrity.
SQL (Structured Query Language): The standard language used for manipulating and managing relational databases.
Backup and Recovery: Key strategies for data preservation involving regular backups and comprehensive disaster recovery plans.

Refers to the distribution of computing services via the internet, providing on-demand resource access.
IaaS (Infrastructure as a Service): Offers virtualized computing resources, exemplified by AWS EC2.
PaaS (Platform as a Service): Supplies tools and frameworks for application development online, such as Google App Engine.
SaaS (Software as a Service): Delivers software applications through the internet, with examples like Microsoft Office 365.
Public Cloud: Services accessible over the public internet and available to any user.
Private Cloud: Exclusively used by a single organization, with management done either internally or by a third party.
Hybrid Cloud: Combines features of public and private clouds, enabling data and application sharing between environments.
Key benefits include scalability for adjusting resources based on demand, cost efficiency reducing on-site hardware needs, and accessibility allowing services to be utilized from anywhere with internet access.