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Glossary
Callback function

Callback function

A callback function is a function that is passed as an argument to another function and executed upon completing the latter’s task. 

In programming, developers use callback functions to carry out another function when specific predetermined conditions — such as task completion, data arrival, or error occurrences — exist. 

Programming languages such as JavaScript and Python use callback functions. JavaScript uses them in event handling, like when a user clicks a button and calls a function to execute a specific task, such as updating the contents of a website. The program executes the callback function once the task is complete. Python uses callbacks in libraries and frameworks like Flask to complete a function after processing a request.

Callback functions allow developers to control the flow of execution to create more efficient and flexible programs. They enable developers to run specific tasks while the program continues to run and initiate other operations upon completion of the task.

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Other glossary terms

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Minified code

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Minified code refers to the process of removing unnecessary characters and whitespace from the source code file without affecting its functionality.

Username

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The ID used to log into your Webflow account.

JPEG

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Short for Joint Photographic Experts Group, JPEG is a file format that uses lossy compression to maintain manageable file sizes without compromising image quality.

Password protection

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Password protection is a security feature restricting certain website areas to authorized users, requiring a secret phrase or key to access them.

Read-only link

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A way for others to test/debug your Webflow site in the Designer without being able to save or make permanent changes.

Element breadcrumbs

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A navigational aid that displays in the bottom of the Webflow Designer to help you keep track of the element you're interacting with in relation to its hierarchy.

Padding

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Padding is a CSS property defining the space between an element's borders and its content.

External link

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External links direct users to different websites and impact a site's search engine visibility and rankings.

Form button

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A form element that lets website visitors submit data to your form handler.

Java

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Java is an object-oriented programming language for building dynamic, interactive web applications across platforms

Pages panel

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A panel in the left toolbar where you can add static pages and folders to your Webflow site. You can also manage and access Utility pages and Collection pages.

Below the fold

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Below the fold refers to the lower portion of a webpage that isn’t immediately visible to visitors upon loading until they scroll down.

Parent folder

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A parent folder is a directory containing one or more folders and files.

ALPN

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ALPN stands for Application-Layer Protocol Negotiation. It’s a Transport Layer Security (TLS) extension that aids client and server identification during secure data transfers.

Color wheel

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The color wheel shows several colors in a circle to represent primary, secondary, and tertiary colors and their relationships.

Right padding

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The inside spacing between the right border of an element and the elements inside it.

Google Universal Analytics Tracking ID

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A unique ID you can use to link your Google Analytics account to your Webflow site.

Undo

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To move backward one step while making changes to a Webflow site.

Collection field

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An individual field within a Collection. You'll select which fields to display in dynamic Collection lists and Collection pages.

Argument

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An argument is an independent value a function receives to deliver a specific output.

Component Module

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A section in the Add Panel that houses pre-built Webflow elements such as sliders, tabs, and lightboxes.

Browser

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A browser, or web browser, is a software program that allows users to access, navigate, and interact with websites on the internet.

Dither

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Dithering is a design technique that simulates additional colors on a display to smooth transitions in images with limited color palettes.

RSS

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Really Simple Syndication (RSS) is a web format that automatically distributes frequently updated content to subscribers, eliminating the need for subscribers to check the website manually to stay up to date.

Position section

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A section in the Style panel that houses CSS properties related to the positioning of an element.

Minimized CSS

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A method of lowering the file size of your stylesheet(s) by removing all white space from your CSS files.

CSS preprocessor

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A CSS preprocessor is a program that helps developers write Cascading Style Sheets (CSS) by providing advanced features such as variables, functions, and nesting.

AJAX

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Asynchronous JavaScript and XML (AJAX) is a web development approach that combines technologies to allow web content to update without reloading.

Unpublished change

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A change that has been made in the Webflow Editor but will not appear on the live website until it’s published. You can track any unpublished changes on the bottom right of the Editor toolbar.

Parent

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The element directly above in the hierarchy tree.

Pagination settings

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Through the pagination settings, you can preview Collection list pages by choosing the page number from the page dropdown list, or you can switch to the previous or next page using the arrow keys.

Account notifications

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Account notifications update you about activity in your account. New notifications appear on your Webflow Dashboard after you log in.

Site plan

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A Webflow plan that you can add/apply to individual sites. You’ll receive access to different site and hosting features based on your Site plan.

Cipher

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In cryptography, a cipher is a digital security algorithm that encrypts and decrypts data.

Flex-basis

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Flex-basis is a CSS property used in flexboxes that sets the initial size of a flex item before it grows or shrinks.

CSS Filters

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CSS filters apply visual effects to HTML elements and their children using Cascading Style Sheets (CSS).

Forms section

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A section of the Add panel that houses form elements like inputs, checkboxes, and radio buttons.

Heading

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A heading is a text element that provides a title or headline for a section of content on a webpage. These elements guide users and search engines through your content.

Blog

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A blog, short for weblog, is a website or webpage where an individual or group regularly shares content about specific topics, typically in reverse chronological order.

Collection

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A content type (blog posts, recipes, etc.) represented by a group of fields you define. Once created, you can add individual Collection items.

Locked site

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When you have more unhosted sites in your Dashboard than your Workspace plan allows, those additional sites past your limit will be “locked” until you upgrade your plan. When you upgrade, you’ll be allowed more unhosted sites (up to the limit for your Workspace plan) and will be able to access your previously locked sites.

Element

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Elements are individual HTML components that constitute a webpage’s structure and contents.

Designer

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The main interface where you can build sites.

GIF

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A GIF (Graphics Interchange Format) is a digital image format that uses multiple frames of an image or soundless video to create a short, looping animation.

Width: auto

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The way browsers calculate an element's width automatically where Block level elements fill the available space of its parent and Inline elements shrink to the size of its children/content.

Height: auto

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The "height: auto" CSS property automatically adjusts an element’s height based on its content.

Network Address Translation (NAT)

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NAT (Network Address Translation) is a technique that enables communication between devices with private internet protocol addresses and the public internet.

Collection list layout

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Lets you control how Collection items display inside a Collection list. The default layout option has each item covering the full width of the parent element. You can change this to display Collection items in 2, 3, 4, or 6 columns.

Abstraction

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In object-oriented programming (OOP), abstraction conceals irrelevant details so they don’t interfere with the task at hand.

Second-level domain (SLD)

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A second-level domain (SLD) is the part of a domain name that precedes a top-level domain (TLD).

Headless CMS

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A headless content management system (CMS) separates the front-end presentation layer from the back-end management layer, allowing for more flexible content delivery.

ID selectors

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You can assign element IDs from the Element settings panel in the Designer. ID selectors are useful for HTML anchors, linking to page sections, or for custom code.

Webflow Support

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The place to go when you need help using Webflow.

Valid

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A valid CSS pseudo-class is a keyword that enables styling HTML elements based on their state or position in the document structure or web page.

Behavioral targeting

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Behavioral targeting is a marketing technique that leverages user data to deliver personalized ads to drive conversions.

Publish destination

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The specific domain or subdomain where your Webflow site is displayed.

Encapsulation

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Encapsulation is an object-oriented programming (OOP) process that combines functions and the data they manipulate into a single entity.

Dashboard

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From your Dashboard, you can access, create, and manage all your sites.

Character encoding

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Character encoding is the process of representing characters (such as “a” or “3”) in a particular way, such as text on a computer screen.

Class

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A class is a template that defines variables for objects with similar properties.

Flex-align

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A flexbox property that lets you customize the alignment behavior of flex children, based on the cross-axis of the flex container. The cross axis is the opposite of the flex-direction property, so if you set the direction to vertical, the cross axis is horizontal. Options include start, center, end, baseline, and stretch.

Mobile (landscape) breakpoint

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A Webflow canvas setting that lets you create styles for viewports with a minimum width of 480px and a maximum width of 767px. Also known as the mobile landscape media query.

Primitive

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A primitive is the simplest JavaScript data type, representing fundamental values that do not encapsulate any object, method, or property.

Favicon

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A 16x16 px image that displays in browser tabs, bookmarks, and other browser areas. It's typically a simplified version of the site's logo.

Optimization

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Optimization is a systematic approach to improve a website's appearance, functionality, and visual appeal to enhance the user experience, improve search engine rankings, and achieve business objectives.

Preview mode

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A feature that allows you to see how your site would be displayed in a browser without needing to publish your site or leave the Designer.

Constant

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In coding, a constant is a fixed value that can’t change, no matter where it appears or what the program uses it for.

Return on investment (ROI)

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Return on investment (ROI) is a metric evaluating the profitability or gain of a venture.

Style Manager

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The third tab in the right-side panel where you can rename element classes, preview your class and tag styles, search for classes and tags, and delete any classes that aren’t in use.

Callback function

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A callback function is passed as an argument to another function and executed upon completing the latter’s task.

Div block

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A generic element that is typically used to group content, or when no other element is specifically or semantically suitable. Div blocks have no effect on the content or layout until styled with CSS.

Unbranded form submission notification

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Form submission notifications that have no reference to Webflow (e.g., notifications sent from “no-reply@webforms.io” instead of “no-reply@webflow.com”).

Left margin

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Left margin is a CSS property that defines the space between an element's left edge and its surroundings.

Margin

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Margins are an essential spacing element of web design, dictating the amount of whitespace between a box and its surroundings.

Editor toolbar

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The toolbar that appears at the bottom of the Editor. From here, you can access the various Editor panels to manage page settings, dynamic content, forms, and your Editor account. You can also see and publish the changes you make through the Editor.

UI state

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The UI state changes how Collection lists display when you’re designing. The Items state is the default option, and shows the items that you have within the Collection. The Empty state doesn’t show these items and gives the designer the opportunity to design for a circumstance if/when there is no data to be displayed in the Collection list.

Backup

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A backup is a copy of data stored in an alternate location, including hard drives, cloud servers, or network-attached storage (NAS) servers.

Export

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A downloadable ZIP file that contains your Webflow site's HTML, CSS, JS, and image files.

Responsive design

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Responsive web design (RWD) is a web development and design approach to create websites, applications, and user interfaces (UIs) that display and function effectively on any device or screen size.

Static page

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A static page is a document with fixed content that makes up an individual web page on your site.

Smoke test

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A smoke test, also called build verification testing or confidence testing, is a preliminary examination to determine the basic functionality of a software, website, or application.

Drafted pages

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You can exclude pages from being published to your site by setting them as drafts. These can be unfinished pages, internal pages such as style guides, archived pages saved for backup, etc. Learn more about drafted pages.

Serialization

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Serialization is the process of converting data into an optimized format for storage, transmission, and sharing.

Control flow

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The control flow is the order in which a computer program executes its instructions or statements, guided by control structures.

Header

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A header is a section at the top of a webpage.

Slider

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A slider is an interactive design element for scrolling through images, videos, and other multimedia content.

Custom font

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A custom font is any non-system-default typeface you manually upload to your website.

Localization

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Localization (l10n) involves adapting digital content and applications to meet a specific region or culture’s language and conventions.

Comment

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A comment is a text note in source code that offers context, internal information, or other guidance to any developers using it.

Element settings panel

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The second panel on the right side of the Designer. Here, you can change element-specific settings such as the element ID, Custom attributes, Search index settings, Editor settings, etc. You can learn more about the element settings for a specific element by searching for the element’s name on Webflow University.

Paragraph

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A typography element used for displaying multi-sentence text content.

SSL

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SSL (secure socket layer) is the standard method for establishing an encrypted link between a web server and a browser.

Bundling

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Bundling, or bundle pricing, is a pricing technique in which retailers sell products together at a lower price than they would be sold at individually.

Paginate items

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This checkbox allows you to enable or disable pagination on the selected Collection list.

Text link

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A typography element that is used to link to other pages or sections of a webpage.

Child

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A child element is an element nested within a parent element in a hierarchy.

Dynamic element

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Dynamic elements are web page components that can change based on user interaction or external factors, like a live news feed, without requiring a page refresh or reload.

Sorting Collection lists

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You can sort your Collection items in multiple ways — select the field from the Collection you wish to filter from, then select the ordering option.

Inheritance dropdown

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A dropdown menu that displays all the selectors that affect a given element.

Collection list

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A Collection list is a Webflow element that lets you dynamically display content from a CMS Collection.
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