The wiki · page 12 of 25

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08 — Web Tech

What Is MongoDB?

MongoDB is a popular open-source NoSQL database that stores data as flexible, JSON-like documents instead of rigid rows and tables. Each document can hold nested fields and vary in structure, so developers can change their data's shape without schema migrations. This suits projects with evolving requirements or rapid prototyping, such as catalogs or user profiles. MongoDB scales horizontally and anchors the MEAN and MERN JavaScript stacks. Its main tradeoff is weaker support for the complex multi-table relationships that SQL databases handle so naturally.

UPDATED 2026-07-10 · READ →

What Is Redis?

Redis is an open-source, in-memory data store that keeps information in RAM rather than on disk, which makes it extremely fast. Web applications use it mainly as a cache — storing results of slow queries or rendered pages so repeat requests return in microseconds — and to hold sessions, queues, and rate-limit counters. Because memory is volatile, Redis can optionally persist to disk, but its primary job is speed, not storage. It sits alongside a database like PostgreSQL or MySQL to offload work and keep busy sites fast.

UPDATED 2026-07-10 · READ →

What Is Docker?

Docker is a tool that packages an application with everything it needs to run — code, libraries, and settings — into a standardized unit called a container. That container runs the same way on a laptop, a test server, and production, ending the classic "it works on my machine" problem. Docker containers are lightweight and start in seconds because they share the host OS kernel instead of bundling a full OS like a virtual machine. It is now a standard way to build, ship, and deploy web applications consistently.

UPDATED 2026-07-10 · READ →

What Is a Container?

A container is a lightweight package that bundles an application with its code, libraries, and configuration so it runs reliably in any environment. Unlike a virtual machine, a container shares the host operating-system kernel instead of its own, so it starts in seconds and uses far less memory and disk. Containers isolate applications from one another, letting many run side by side on one server without conflicts. They are the basic building block of modern deployment, created with tools like Docker and managed at scale by orchestrators such as Kubernetes.

UPDATED 2026-07-10 · READ →

What Is Kubernetes?

Kubernetes, often shortened to K8s, is an open-source system that automates deploying, scaling, and managing containerized applications across a cluster of servers. Instead of manually starting and watching containers, you declare the desired state — how many copies to run and the resources each needs — and Kubernetes schedules the containers, restarts failed ones, balances traffic, and scales to match demand. Originally built by Google, it is now the industry standard for running containers at scale. It is powerful but genuinely complex, and most small businesses never need it directly.

UPDATED 2026-07-10 · READ →

What Is Serverless?

Serverless is a cloud computing model where you run code without managing servers yourself. Despite the name, servers still exist — the cloud provider runs, scales, and maintains them invisibly, and you supply small functions that run in response to events like a web request. You pay only for the compute time your code actually uses, often billed by the millisecond, and it scales automatically from zero to thousands of requests. Common examples include AWS Lambda, Cloudflare Workers, and Vercel Functions. It suits variable or unpredictable workloads and lightweight APIs.

UPDATED 2026-07-10 · READ →

What Is an API Endpoint?

An API endpoint is a specific URL that a program calls to send or retrieve data from another system. Each endpoint represents one resource or action — for example, /users returns a list of users, and /orders/42 returns order number 42. A client sends an HTTP request, using a method like GET or POST, to the endpoint, and the server replies with a structured response, usually JSON. Endpoints are how two applications talk to each other over the web.

UPDATED 2026-07-10 · READ →

What Is an API Key?

An API key is a secret string of characters that identifies and authorizes an application when it calls an API. It works like a password for software: the calling program includes the key with each request, and the server checks it before returning data or performing an action. Keys let a provider know who is calling, apply the right permissions, enforce rate limits, and cut off abuse. Because anyone holding the key can use it, keeping it secret is essential — a leaked key is a leaked account.

UPDATED 2026-07-10 · READ →

What Is a Rate Limit?

A rate limit is a cap on how many requests a user, app, or IP address can make to a server or API within a set time window — for example, 100 requests per minute. When the cap is exceeded, further requests are temporarily refused, usually with an HTTP 429 'Too Many Requests' response. Rate limits protect services from overload, abuse, and runaway costs, keep performance fair across users, and blunt attacks like brute-force login attempts and denial-of-service floods. Nearly every serious API and login system enforces them.

UPDATED 2026-07-10 · READ →

What Is a Cron Job?

A cron job is a task scheduled to run automatically at set times on a server, without anyone triggering it manually. The name comes from cron, a time-based job scheduler built into Unix and Linux systems. You define when a job runs — every night at 2 a.m., or every Monday — and the server runs the command on that schedule. Websites use cron jobs to automate backups, send emails, clear caches, generate reports, and sync data on a reliable timer.

UPDATED 2026-07-10 · READ →

What Is a Reverse Proxy?

A reverse proxy is a server that sits in front of one or more web servers and forwards incoming visitor requests to them, then returns the servers' responses to the visitors. To the outside world it looks like the website itself, hiding the real servers behind it. Reverse proxies handle jobs such as distributing traffic across servers, caching content for speed, terminating HTTPS, filtering malicious requests, and routing URLs to different back-end services. Popular examples include Nginx, HAProxy, and Cloudflare — a core building block of fast, secure websites.

UPDATED 2026-07-10 · READ →

What Is Load Balancing?

Load balancing is the practice of spreading incoming website or application traffic across multiple servers so no single server becomes overwhelmed. A device or service called a load balancer sits in front of your servers and distributes each request among them, keeping response times low and preventing any one machine from becoming a bottleneck. It also improves reliability: if one server fails, the load balancer routes traffic to the healthy ones, so the site stays online under heavy demand.

UPDATED 2026-07-10 · READ →

What Is a Service Worker?

A service worker is a script that a browser runs in the background, separate from a web page, acting as a programmable proxy between the site and the network. It enables features that once required a native app: offline access, faster repeat loads through caching, background sync, and push notifications. Because a service worker sits between your site and the internet, it can intercept network requests and serve cached responses, which is the foundation of Progressive Web Apps. It runs only over HTTPS for security.

UPDATED 2026-07-10 · READ →

What Is a WebSocket?

A WebSocket is a technology that opens a single, persistent, two-way connection between a browser and a server, so both sides can send messages to each other at any time. Unlike a normal HTTP request, where the browser asks and the server answers once, a WebSocket stays open, letting the server push data instantly without the browser asking again. This makes it the standard foundation for real-time features: live chat, instant notifications, collaborative editing, live sports scores, and streaming dashboards, where waiting for the next page refresh would feel broken.

UPDATED 2026-07-10 · READ →

SSG vs SSR: What's the Difference?

SSG (static site generation) and SSR (server-side rendering) are two ways to produce a web page's HTML. With SSG, pages are built once ahead of time, at deploy, and served as ready-made files, so they load fast but show the same content until you rebuild. With SSR, the server builds each page fresh on every request, so content is always current but each visit does more work. SSG suits content that changes rarely, like marketing and blog pages; SSR suits pages that must reflect live, personalized, or frequently changing data.

UPDATED 2026-07-10 · READ →

What Is a Web Standard?

A web standard is an agreed-upon technical specification that defines how web technologies like HTML, CSS, and JavaScript should behave, so any browser can render the same page consistently. These rules are published by bodies such as the W3C and WHATWG, then implemented by browser makers. Standards are what let a site built once work across Chrome, Safari, Firefox, and Edge without separate versions. Without them, the web would fracture into incompatible, browser-specific pages that only worked in one place.

UPDATED 2026-07-10 · READ →

What Is Online Appointment Scheduling?

Online appointment scheduling is a website feature that lets customers book, reschedule, or cancel appointments themselves, at any hour, without calling. It shows your real-time availability, collects the details you need, and confirms the booking automatically, often adding it to your calendar and sending reminders. For service businesses, salons, medical offices, contractors, consultants, it replaces phone tag with self-service convenience, captures bookings around the clock, and reduces no-shows through automated reminders. Scheduling can be built with dedicated tools or embedded into a website through a widget or integration.

UPDATED 2026-07-10 · READ →

What Is a Patient Portal?

A patient portal is a secure website or app that gives patients online access to their healthcare information and services. Through a private login, patients can view test results, request prescription refills, message their provider, book or change appointments, complete intake forms, and pay bills, without calling the office. Portals are common in medical, dental, and specialty practices and are typically part of an electronic health record system. Because they handle sensitive health data, patient portals must protect privacy and security under laws like HIPAA in the United States.

UPDATED 2026-07-10 · READ →

What Is a Membership Website?

A membership website is a site where some or all content and features are locked behind registration or payment, so only members can access them. Visitors sign up, often paying a recurring subscription, to unlock exclusive articles, courses, videos, community forums, downloads, or services. Membership sites turn a website into a recurring-revenue business, common for online courses, professional communities, content publishers, and clubs. They rely on user accounts, access control that gates protected content, and usually a payment system that handles subscriptions, renewals, and cancellations automatically.

UPDATED 2026-07-10 · READ →

What Is a Directory Website?

A directory website is a searchable online listing that organizes many businesses, people, products, or resources into browsable, filterable entries. Think of it as a structured phone book for the web: each listing has its own profile with details like name, category, location, hours, and contact information, and visitors search or filter to find what they need. Examples include local business directories, doctor finders, and vendor marketplaces. Directory sites earn money through paid listings, ads, lead fees, or subscriptions, and they rely on solid database structure and search to stay useful.

UPDATED 2026-07-10 · READ →

What Is a Booking Website?

A booking website is a site built so that its main action is letting customers reserve and schedule something, an appointment, table, room, class, or service, directly online. Instead of forcing people to call, it shows real-time availability on a calendar, lets them pick a slot, collect their details, take payment or a deposit if needed, and send automatic confirmations and reminders. Common examples include salon appointment sites, restaurant reservations, hotel bookings, and class sign-ups. The booking engine, availability logic, and confirmations are the heart of the site, not an afterthought.

UPDATED 2026-07-10 · READ →

What Is a Reservation System?

A reservation system is software that manages the booking of a limited resource, tables at a restaurant, rooms at a hotel, seats in a class, or time slots with a professional, so customers can reserve online and the business never double-books. It tracks what is available in real time, holds a slot the moment someone reserves it, records who booked what and when, and sends confirmations and reminders. Integrated into a website, it replaces phone-and-paper booking with a self-service calendar that staff and customers share, reducing errors, no-shows, and administrative time.

UPDATED 2026-07-10 · READ →

What Is Real Estate IDX?

Real estate IDX, or Internet Data Exchange, is the system that lets a real estate agent or broker display up-to-date MLS property listings directly on their own website. Through an IDX agreement and data feed, an agent can show homes for sale from across their local Multiple Listing Service, not just their own listings, with search, filters, and photos. The feed updates automatically so listings stay current. IDX keeps house hunters on the agent's site instead of a portal, capturing leads while following MLS display rules about attribution and permitted use.

UPDATED 2026-07-10 · READ →

What Is an MLS Integration?

An MLS integration is the technical connection between a real estate website and a Multiple Listing Service data feed, so property listings flow automatically from the MLS onto the site and stay current. It pulls listing data, prices, photos, status, and features, through a standardized feed such as the RESO Web API, then displays it in searchable pages. MLS integration is the engine behind IDX and VOW real estate sites. Done well, it keeps thousands of listings accurate without manual entry, follows MLS display rules, and powers the search experience that turns visitors into leads.

UPDATED 2026-07-10 · READ →

What Is a Service Menu Page?

A service menu page is a website page that lists the services a business offers, usually with a short description, duration, and price for each, laid out like a menu so customers can quickly compare and choose. It is common for salons, spas, clinics, barbershops, and other service businesses where clients pick from set treatments. A good service menu page groups offerings clearly, shows honest pricing, and makes it easy to book or enquire. Done well, it answers the customer's core question, what you offer and what it costs, and drives them toward booking.

UPDATED 2026-07-10 · READ →

What Is a Gallery Website?

A gallery website is an image-forward site built to showcase visual work, where photographs or graphics are the main content and the design gets out of their way. Photographers, artists, designers, venues, and other visual businesses use them to display projects, products, or spaces in high quality. A gallery site organizes images into collections, presents them with fast-loading layouts like grids and lightboxes, and pairs the visuals with just enough context and a clear way to enquire or buy. The goal is to let strong imagery do the selling while staying fast and easy to browse.

UPDATED 2026-07-10 · READ →

What Is a Portfolio Website?

A portfolio website is a site built to display a person's or company's body of work in order to win new clients, jobs, or projects. It curates selected examples, case studies, designs, photos, or writing, and presents them with enough context to show skill and results. Freelancers, agencies, designers, developers, and photographers use portfolio sites as their proof of ability and their pitch. Unlike a simple gallery, a portfolio adds narrative, the problem, the work, the outcome, and a clear call to hire, turning examples of past work into future business.

UPDATED 2026-07-10 · READ →

What Is a Service Area Map?

A service area map is an interactive or illustrated map on a website that shows the geographic regions a business serves. It helps visitors instantly confirm whether they fall within coverage - by city, county, zip code, or a shaded radius - before they call or request a quote. Common on home-services, delivery, and mobile-business sites, it reduces wasted enquiries from outside the area and supports local SEO by clearly naming the places served. It can be a simple graphic or a live, zoomable map.

UPDATED 2026-07-10 · READ →

What Is a Financing Calculator?

A financing calculator is an interactive on-site tool that estimates the monthly payment for a purchase or project, based on inputs like total price, down payment, interest rate, and term. It lets visitors see an affordable-looking monthly figure - for example turning a $9,000 HVAC system into roughly $180 a month - which lowers sticker shock and encourages higher-ticket enquiries. Common on home-improvement, automotive, medical, and big-ticket service sites, it is an estimate for guidance only, not a binding loan offer.

UPDATED 2026-07-10 · READ →

What Is a 500 Internal Server Error?

A 500 Internal Server Error is a generic HTTP status code meaning the web server hit an unexpected problem and could not complete the request, but cannot say exactly what went wrong. It is a catch-all for server-side faults - a code bug, a broken plugin, a misconfiguration, or an exhausted resource - not a problem with the visitor's browser. Visitors see a blank or error page instead of your content. The real cause almost always lives in the server logs, which is where diagnosis begins.

UPDATED 2026-07-10 · READ →

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