What is GitHub?
And the rest of the jargon.

The place where your project's code is stored, with the full history of every change alongside it. Compare it to Google Drive for code: you see who changed what and when, and you can go back to yesterday if something goes wrong. Important to you for one reason: if the code sits in your GitHub account, you do not depend on the developer who wrote it.

One project on GitHub: all the files of your website or application together. If someone asks whether you have 'access to the repo', they mean: can you reach your own code.

The text files your site or application is built from. Without source code you only have the end result and nobody can change anything about it anymore, including you. That is why it should be yours on delivery, not the agency's.

A collection of ready-made building blocks developers start with, so every project does not begin at zero. Next.js and React are frameworks. The alternative is an in-house system only the maker understands, and that is exactly what you do not want.

The most used way to build screens that respond without the page reloading: filters, forms, dashboards. Made by Meta, free to use, known to practically every web developer.

The framework on top of React that makes sure your pages also load fast and are findable by Google. React alone often produces a site that is empty to a search engine; Next.js solves that.

Software whose code is public and that you may use for free, commercially too. Next.js, React and most of the technology I use are open source: no licence costs, no supplier who can raise the price.

Frontend is everything you see on screen: buttons, text, colours. Backend is what you do not see: the database, the calculations, the emails being sent. A 'simple' button can therefore be a lot of work if there is backend behind it.

Where your application's data lives: customers, orders, invoices, settings. A website without a database shows fixed text; the moment someone can enter something that still exists tomorrow, a database is involved.

A fixed agreement two systems use to exchange data with no human in between. Your accounting package automatically receiving an invoice from your webshop: that runs over an API. If a package has 'no API', connecting suddenly gets much more expensive.

A signal a system sends by itself the moment something happens, instead of your system having to ask every minute whether there is news. A payment arriving at Mollie and immediately flipping the status of your order: that is a webhook.

Two systems using each other's data, for example your site and your CRM. This is usually where the time goes, not the design, because every existing system has its own peculiarities.

The computer that serves your website to the world day and night. You rent it monthly, usually for a few tens to a few hundred euros, depending on how many visitors and how much data pass through.

Your address on the internet, for example webframer.nl. You rent it annually, separately from your hosting. Make sure it is in your name and your account, not your agency's; getting a domain back is one of the most unpleasant conversations there is.

The phone book of the internet: it translates your domain name to the computer your site sits on. If you move to different hosting, you change DNS settings. Changes can take up to a day before everyone sees them.

The padlock in the address bar. It encrypts traffic between visitor and site, is free these days and mandatory: without https browsers put a warning on your site and Google ranks you lower.

A network of servers spread across the world that puts copies of your images and pages closer to the visitor. You notice the difference mostly when your visitors come from multiple countries.

Putting a change live. In a modern setup that is a one-minute action, automatic, with the option to roll back within a minute if something turns out broken.

A second, shielded copy of your site where new things are tested first. That way visitors never see a half-finished feature, and you can look along before anything really goes live.

A copy of your site and database from yesterday, last week and last month. More important than people think: most disasters are not being hacked, but someone accidentally deleting something.

The percentage of time your site is reachable. 99.9% sounds like almost always and means roughly eight hours a year down. With a webshop or portal that is the difference between inconvenience and lost revenue.

Content Management System: the admin screen where you change text, photos and pages yourself without a developer. Useful if something changes weekly. If something changes twice a year, a CMS is maintenance you never earn back.

Everything that makes people find you through Google without paying per click: technology, speed, structure and above all copy that answers what someone is searching for. It is not a button you switch on, it is about three months of patience.

The three numbers Google measures how fast and stable your site feels with: how quickly the largest block appears, how quickly the site responds to a click, and whether the page jumps under your finger. If those are in the red, it costs you rankings.

A site that adapts to the screen: phone, tablet, laptop. Not an extra, just the basics, most of your visitors are on a phone.

Being usable for people with a disability: sufficient contrast, operable with a keyboard alone, readable by a screen reader. Legally required for government and semi-government, and simply sensible for everyone else.

The percentage of visitors who do what you have the site for: request a quote, call, order. Ten percent more conversion is usually cheaper to get than ten percent more visitors.

Software as a Service: software customers pay for monthly rather than once, running in the browser. Think Exact or Teamleader. If you build this yourself, subscriptions, invoicing and multiple customers side by side come into play.

A shielded part of your site where customers log in and see their own quotes, invoices or project status. It exists to prevent the questions that now come in by email and phone.

Logging in with your password plus a code from your phone. The moment personal data or money sits behind a login, this stops being a luxury.

Building software by describing what you want in plain language and letting the AI write the code. Works surprisingly well up to a demo, and after that usually gets stuck on logins, payments and security, precisely the parts where going wrong costs money.

Tools you click a working first version together with, without programming knowledge. Fine for testing an idea. They produce real code, so what you make there can usually be taken over and finished rather than thrown away.

The instruction you give an AI. In this trade the quality of the instruction decides the quality of the result: 'make a webshop' produces something different than three paragraphs on exactly what should happen when a payment fails.

Large Language Model: the type of AI behind ChatGPT and Claude. It predicts text, and code is text, which is why it can program. It just does not know when it is making something up, and that is why someone has to check it.

Quick choices today that cost you time tomorrow. Every codebase has it; it only becomes a problem when every new feature takes longer than the last. In AI-generated projects it stacks up faster than people expect.

Cleaning up code without anything changing on the outside. Feels like delivering nothing and is the difference between a project you can still build on in a year and a project that has to be redone.