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Glossary
Shim

Shim

A shim is a code snippet enabling modern web features to function within older programming or browsing environments. Distinct from a polyfill — a specific type of shim that introduces non-native functionality to a web browser — shims allow newer web features to operate within outdated browsers.

As web browsers and applications evolve, shims address the compatibility issues that older browsers often encounter due to their lack of native support for recent web features, such as HTML5, CSS3, and JavaScript APIs.

Web developers leverage shims to ensure broad interoperability, making their applications accessible across various devices and browser versions. They help businesses appeal to a wider audience, guaranteeing seamless functionality regardless of the user’s technical setup.

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Other glossary terms

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Empty state

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The state displayed when a Collection contains no Collection items, which gives you the opportunity to design for a situation where there's no content to display. Check out the Empty States blog for inspiration.

Collection list

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

JavaScript

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JavaScript is a programming language web developers use to create dynamic interactions and effects for web pages and applications.

Empty elements

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Empty or void elements are HTML elements that don’t require a closing tag because they contain no content.

X-Ray mode

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A grayscale view of your site’s canvas that visually displays each element’s border, margin, and padding when hovered over.

Display: none

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Display: none is a CSS property that hides website elements. This code tells the document flow to ignore the element entirely, making it invisible.

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.

Mobile (portrait) breakpoint

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A Webflow canvas setting that lets you create styles for viewports with a minimum width of 240px and a maximum width of 479px. Also known as the mobile portrait media query.

Top padding

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

Top of the funnel

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Top of the funnel (TOFU) refers to the initial marketing funnel stage where potential customers become aware of a brand’s existence.

Collection item

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An individual item within a Collection. For example, in a “Blog Posts” Collection, the Collection items are individual blog posts.

DHTML

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DHTML, or Dynamic HTML, is a web-development technique combining HTML, CSS, and JavaScript to create dynamic, interactive web pages and complex web applications.

Video

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A Webflow element that displays externally hosted videos such as YouTube and Vimeo.

Zapier

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A web app that helps you connect multiple third-party services together based on triggers and actions.

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.

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.

Document type definition (DTD)

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A document type definition (DTD) defines the structure, validity, and attributes of standard generalized markup language (SGML) documents, such as GML, HTML, and XML.

Duplicate element

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To copy an element and its content, styles, and settings.

Ancestor

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Any element that is further up the element hierarchy of the document tree. For example, the Body element is the ancestor of all elements on the Designer canvas.

CMS section

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A section in the Add panel that contains elements associated with the CMS.

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.

Graphical User Interface (GUI)

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A Graphical User Interface (GUI) is a visual medium that enables visual interaction with software applications or electronic devices through elements like icons, buttons, and menus.

List

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An element that contains ordered (numbered) or unordered (bulleted) lists.

Common targets

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All elements on the page targeted by the same selector.

Username

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The ID used to log into your Webflow account.

Columns

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Columns let you create sections of content that sit side by side on your website, like the columns in newspapers. You can choose how many columns you want and their widths. You can also control how they display on smaller screens — such as stacking them.

Display: flex

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The most flexible display property in CSS is the aptly named display: flex, which allows you to create flexible layouts with elements that you can align and distribute vertically or horizontally.

Canvas

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The <canvas> tag in HTML5 creates a container for dynamic graphics and image rendering on a webpage.

Publish destination

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

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.

Switch field

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Available in CMS Collections. This field offers you a powerful filtering tool for Collection items. For example, you could create a switch labeled "Featured?" for Blog Posts, and then switch on the toggle to showcase particular posts.

Padding

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

Head code

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Custom code that's added just before the closing </head> tag in your site's HTML file. Learn more about custom code in head and body tags.

Link block

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A link block operates much like a div block, an HTML element for grouping and organizing other HTML elements (like text, images, and forms) into block-level containers. But in the case of a link block, what’s inside the block becomes a link.

Inheritance

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Inheritance describes a principle where child elements adopt the style properties of parent elements.

Modal window

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A modal window (or modal) is a web element that displays above all content and restricts user interaction until it’s manually dismissed.

User interface (UI)

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A user interface (UI) is any visual element humans interact with on a device, webpage, or application.

CRLF

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On Windows-based systems, the sequence of two ASCII characters representing a line break in text files is called "Carriage Return, Line Feed," or CRLF.

Literal

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In JavaScript, literals are fixed values written directly into the code.

Em

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An em in CSS is a scalable and relative unit of measurement that defines the size of an element relative to its parent's font size.

Reference field

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A CMS field used in Collections. This powerful field allows you to link to other Collections within your website to populate fields in Collection lists and Collection pages.

Bug

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A bug is an error, fault, or flaw in an application or software that causes the program to behave unexpectedly, often producing inaccurate and invalid output.

URL

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A Uniform Resource Locator (URL) is a standardized web address format that allows users to identify and access an online resource.

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.

Key

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A key, or web key, is a unique identifier that authorizes access to a webpage or service.

Display: inline-block

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The display: inline-block CSS property defines an element’s appearance and behavior. CSS designers use this code to create website layouts.

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.

Display: grid

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The display: grid CSS property defines a website element (such as a button or header) as a grid container.

Height: auto

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

Ligature

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A ligature in typography groups adjacent letters or characters into one glyph.

Custom font

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

Map

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A Webflow element that embeds an interactive Google Map in your site.

Height

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Defines how tall an element can be. This can be defined in absolute terms (pixels) or relative terms (ems, rems, percentages, viewport-height, or viewport-width).

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.

Style panel

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The first tab in the right-side panel that allows you to assign classes to elements and style them.

Hypertext transfer protocol secure (HTTPS)

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Hypertext Transfer Protocol Secure (HTTPS) is a secure protocol facilitating encrypted exchanges of information between web browsers and servers.

Product attribute

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Product attributes are specific characteristics that define purchasable merchandise or commodities and provide relevant information to customers.

Call stack

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A call stack is an ordered list of the functions (or stack frames) a program has to execute before it returns a result.

Folder

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A folder is a subdirectory of your site's root folder for organizing web pages.

Subdomain

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The part of a domain that comes before the root domain (e.g., blog.yourwebsite.com is a subdomain whereas yourwebsite.com is the root domain).

Behavioral targeting

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

ATAG

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Authoring Tool Accessibility Guidelines (ATAG) are a layered rule-set that influence how designers and developers create a more accessible internet.

Automagically

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Automagically describes complex content or functions that appear as if they were created using magic.

Web server

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A web server is a computer program or hardware device that delivers web content to clients using HTTP. It handles client requests for web pages, images, and videos.

Deep copy

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In programming, a deep copy is a replica of an object that doesn’t share the same references as the original. That way, if you make changes to the duplicate, the original stays the same.

Right-side panel

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The far right vertical panel in the Designer that houses the Style panel, Element settings panel, Style manager panel, and Interactions panel.

Design mode

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The mode that enables a designer to build in Webflow.

Compile time

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Compile time is the length of time it takes for a compiler to convert high-level code into low-level code.

Media section

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A section of the Add panel that holds multimedia elements like images, video, and Lottie animation.

Webflow forum

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The place to go when you need help with your site's design, custom code, etc. Visit the forum.

Percent

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A measurement unit relative to an element's parent.

Domain-Specific Language (DSL)

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A Domain-Specific Language (DSL) is computer script that solves software problems in a specific domain.

Facebook button

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A Facebook button is a clickable element on a website that allows users to connect to or share content on the social media platform.

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.

Shim

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A shim is a code snippet enabling modern web features to function within older programming or browsing environments.

Utility pages

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Utility pages are default, customizable templates for your site’s 404 page, Password page, and Search results page.

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.

Span text

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The span tag is used to style inline-text.

Flex-justify

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A flexbox property that lets you customize the alignment behavior of flex children, based on the main axis of the flex container — that is, whatever you defined as the flex-direction. Options include start, center, end, baseline, and stretch.

Tablet breakpoint

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A Webflow canvas setting for creating styles that affect viewports with a minimum width of 768px and a maximum width of 990px. Also known as the tablet media query.

Descriptor

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A CSS descriptor sets specific properties and values of an at-rule (@-rule) element, dictating its appearance and behavior on a web page.

External link

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

Page name

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The title of a page in your site. This is visible in the Pages panel.

Base tag

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The base tag specifies the base URL for all relative links within HTML code for a specific page or document.

Null

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“Null” represents the absence of a value or the presence of invalid objects in computer science and web development.

Collection limits

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By default, Collection lists display all items in a Collection, but you can add limits to control the number of Collection items that display.

Font weight

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Font weight refers to the thickness or density of a typeface’s strokes.

Object-oriented programming (OOP)

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Object-oriented programming (OOP) is a programming approach that organizes code into self-contained units of data, functions, and behavior.

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.

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.

Hit

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A hit is a request to a web server from a browser for a specific resource.

Text link

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

Dynamic content

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Content you create once, then publish in many different places across your website. As you update this content in the CMS, it automatically updates wherever it exists on your site, making it convenient to create and manage larger websites.

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.

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.

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.

Item state

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The default UI state for Collection lists, which displays the items in the Collection. It is the opposite of the empty state.

Webflow Support

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The place to go when you need help using Webflow.

Navigator

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A navigator, or a navigator window or panel, is a graphical user interface (GUI) that provides an overview of a website's structure and layout.

Plain text field

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A plain text field is an input field for short-form text without formatting or styling.
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