Availability

Definition: Availability refers to the degree to which a system, resource, etc. can be used when needed. It is a crucial metric for measuring the reliability and usability of a product or service, reflecting the ability to meet user needs and operate properly at any time.

Explanation: High availability means that the system is rarely unavailable, minimizing downtime. It is affected by factors like hardware reliability, software stability, and maintenance strategies. For example, in a web application, high availability ensures that users can access the site without frequent disruptions.

Importance: In business, high availability is vital as it impacts customer satisfaction, productivity, and revenue. A system with low availability can lead to lost opportunities, frustrated customers, and damage to the company's reputation.