Hard disk drive
Storage using rotating magnetic platters. Mechanical access affects latency; capacity, reliability and performance depend on the specific model.
Definition and sourcesKNOWLEDGE / FROM A TO Z
Glossary
Technology, explained clearly. Find a term, choose a letter or narrow the topic. Definitions include sources and their review date.
Terms 13 / 685
Clear filtersHigh availability
Designing a service to limit disruption despite component failures. Redundancy needs tested failover and removal of single points of failure; it does not eliminate risk.
Definition and sourcesHosting
Providing resources needed to operate a website or application. Hosting involves more than storage: computing, networking and maintenance matter. Selection depends on project requirements and the provider's responsibilities.
Definition and sources.htaccess
An Apache configuration file affecting a directory when the server permits overrides. It can control redirects and access. It is not universal to every hosting server; Nginx does not read it like Apache.
Definition and sourcesHTTP (HyperText Transfer Protocol)
An application protocol using requests and responses, including for websites and APIs. It defines methods, headers and statuses. Protocol statelessness does not prevent applications from implementing sessions.
Definition and sourcesHTTP 301 (permanent redirect)
An HTTP status indicating a resource has moved permanently. The server normally provides the new address in Location. It is a redirect, not an error, and does not guarantee preserved search rankings.
Definition and sourcesHTTP 302 (temporary redirect)
An HTTP status indicating a temporary redirect while the original address remains the reference. It is not an error. Indexing effects depend on context rather than a blanket rule that 302 never affects search.
Definition and sourcesHTTP 403 (forbidden)
An HTTP status indicating that the server refuses the request, possibly because of permissions or access rules. A TLS certificate failure is not a 403 response. Resolve permissions with the administrator instead of bypassing protections.
Definition and sourcesHTTP 404 (not found)
An HTTP status indicating that a resource was not found or its existence is not disclosed. Check addresses and links. DNS failure happens at a different stage and is not itself an HTTP 404 response.
Definition and sourcesHTTP 500 (server error)
A general HTTP status signalling an unexpected server-side problem. It does not identify a specific cause. Diagnosis requires safe inspection of logs and configuration; updating PHP at random is not a universal fix.
Definition and sourcesHTTP 505 (version not supported)
An HTTP status indicating that the server does not support, or refuses to support, the major protocol version used in the request. It concerns HTTP, not the browser version or a general network outage.
Definition and sourcesHTTPS
HTTP carried over a TLS-protected connection. It protects transmission confidentiality and integrity and supports server authentication. A padlock does not establish the owner's honesty or protect against every application defect.
Definition and sourcesHybrid cloud
An architecture combining private or on-premises environments with public cloud. Integration, management and data flow matter, not merely having two providers.
Definition and sources