Hosting glossary
Concise definitions for servers, hosting and domains. Sourced and regularly refreshed.
Backup strategy
A rule set defining which data is backed up when, where and how often — the proven 3-2-1 rule says 3 copies, 2 media, 1 off-site.
Bare metal
Direct use of physical server hardware without a virtualisation layer — synonymous with dedicated server or root server.
Caddy
Modern open-source web server written in Go that fetches and renews Let's Encrypt certificates fully automatically — configuration in 3 lines instead of 30.
CDN
Content Delivery Network — a distributed network of edge servers that delivers images, CSS, JS and static HTML from the geographically closest location to each visitor.
Cloud server
Virtual server billed by the second, started, stopped, snapshotted and scaled horizontally via the provider's API or web console.
cPanel
Commercial Linux hosting control panel (~$15/month entry) that dominates the US market and shared hosting platforms.
DDoS protection
Measures that protect servers from distributed denial-of-service attacks — usually delivered through provider edge, CDN layer or scrubbing centres.
DNS
Domain Name System — the distributed directory that resolves human-readable domain names (example.com) to IP addresses (203.0.113.42) and makes the entire internet navigable.
DPA (Data Processing Agreement)
Data Processing Agreement under Art. 28 GDPR — mandatory contract between the controller (you) and the processor (hosting provider) on protection and purpose limitation of processed data.
GDPR-compliant hosting
Hosting setup that meets EU GDPR requirements — usually through an EU location, a vetted provider, a Data Processing Agreement and avoidance of US third-country transfers.
Hypervisor
Software layer that splits physical server hardware into multiple isolated virtual machines — the foundation of every VPS and cloud-server platform.
IPv4 vs IPv6
IPv4 (32 bit, ~4.3 billion addresses) has been exhausted since 2011 and is getting expensive; IPv6 (128 bit) offers practically unlimited address space but isn't available everywhere.
KVM
Kernel-based Virtual Machine — the open-source hypervisor built into the Linux kernel that powers most European VPS offers.
Let's Encrypt
Free, automated Certificate Authority that has issued more than 90 % of HTTPS certificates on the public web since 2016 — setup via ACME protocol in minutes.
Load balancer
Network component that distributes incoming requests across multiple backend servers — provides horizontal scaling, failover and even load distribution.
Managed server
Dedicated or virtual server where the provider maintains the OS, updates, security patches and often the web stack — you only manage content and applications.
nginx
Open-source web server and reverse proxy that has powered over 30 % of all websites for years — known for low RAM usage and high concurrent-connection load.
NVMe SSD
Solid-state disk connected via the fast NVMe protocol directly to the PCIe bus — 3–6× higher throughput than classic SATA SSDs.
Object storage
Scalable storage for unstructured files (images, backups, videos) addressed via the S3 API — pricing typically €0.005–0.02 per GB/month.
Plesk
Commercial hosting control panel (~€7/domain/month) that bundles domain, mail, database and web-server management in the browser — the European default at many managed hosts.
RAID
Redundant Array of Independent Disks — a group of drives combined for either data safety (RAID 1/5/6/10), performance (RAID 0) or both.
Reverse proxy
Server sitting between the internet and one or more backend services that accepts requests, forwards them and caches, compresses or encrypts responses.
Root server
Dedicated physical server whose full hardware is exclusively yours — including root access, any operating system and complete control over every CPU cycle.
Shared hosting
Shared hosting plan with a preconfigured web stack (Apache/Nginx, PHP, MariaDB) and an admin panel — no root rights but ready to go instantly.
Snapshot
Point-in-time copy of a virtual machine or volume — created within seconds and just as quickly restorable.
SSL/TLS certificate
Cryptographic proof that a domain belongs to a specific operator — the prerequisite for HTTPS-encrypted connections and the browser padlock.
Storage box
Cheap, classically connected storage (typically 1–20 TB) via SMB/SFTP/FTP/Borg/Rsync, designed for backups and large data archives — no web delivery.
Uptime & SLA
Uptime = percentage availability (99.9 % = max 8.76 h downtime/year); SLA = contractually guaranteed availability with defined credits if missed.
VPS
Virtual Private Server — a virtual machine on shared hardware that behaves like a standalone server with root access.