Definitions beginning with B

B2B

Business to business: activity in which a company primarily sells to other organisations.

In practice: Provide comparison, internal approval information and contact routes for multiple decision makers.

B2C

Business to consumer: activity in which a company sells directly to individuals.

In practice: Check that price, availability, delivery and support are clear at decision time.

Back-end

Server-side part of a website or application: business logic, data access, authentication and processes not directly visible.

In practice: Describe inputs, errors and data to retain before implementing server-side processing.

Backlink

Link on a third-party website pointing to your site. Its relevance and quality matter more than quantity alone.

In practice: examine the linking page’s relevance before considering a metric.

Backup

Backup copy used to restore files, a database or a system after loss or an incident.

Reference: NIST CSRC · Backup · Source consulted 2026-10-31

In practice: Perform a test restore and check that content and database match.

Bandwidth

Connection transmission capacity per unit of time, usually in bits per second. It differs from transferred bytes and latency; high bandwidth does not remove every delay.

Reference: MDN : Bandwidth · Source consulted 2026-10-18

In practice: Measure actual transfer volumes at busy times before sizing a plan.

Banner

Graphic area used for an advertisement, promotion, consent request or important message.

In practice: Check readability, weight and link destination on formats actually distributed.

Baseline

Indicator of a Web feature’s availability across a defined set of popular browsers. Availability labels summarise support over time. They do not replace testing on target devices or checking accessibility, security and performance.

Reference: MDN : Baseline compatibility · Source consulted 2026-10-18

In practice: Record a measure and its context before comparing a new version.

Benchmark

Structured comparison of solutions, performance or practices to identify gaps and improvements.

In practice: compare equivalent journeys and record differences in audience and context.

Bidirectional isolation

Markup isolating a text fragment’s directional context so opposite scripts do not disrupt surrounding punctuation or neighbouring elements. HTML bdi and appropriate dir attributes can support this.

Reference: W3C : Inline bidirectional markup

Source consulted : W3C : Structural markup and right-to-left text · 2026-10-09

Display a Latin name, email and number within Arabic text, then check punctuation, copying and link destinations.

Bing

Microsoft search engine, also used as a source or infrastructure by several search and AI products.

In practice: Check discovery, indexing and page rendering in the engine’s own tools.

Black hat SEO

SEO techniques intended to manipulate search engines by bypassing their rules, with a high risk of visibility loss.

In practice: Assess visibility risk before using a technique intended to manipulate results.

Blog

Publishing area regularly updated with articles, advice, news or viewpoints.

In practice: Define topics, accountable author and review cadence before opening a section.

Booking capacity

Number of appointments an organisation can actually fulfil in a period given its people, equipment, spaces and preparation time.

In practice: count staff, rooms, equipment and preparation time before opening a new booking window.

Booking slot

Time offered for booking after accounting for service duration, staff or resource availability and necessary buffers between appointments.

In practice: try the last available slot from two devices and confirm that only one booking can succeed.

Bot

Automated program performing repetitive tasks such as crawling pages, answering requests or monitoring a service.

In practice: Distinguish useful tasks from harmful traffic using observed behaviour.

Bounce rate

Bounce rate: a metric whose definition varies by tool, generally related to sessions without meaningful interaction or engagement.

In practice: Compare this metric with the page task: a quick answer can be a successful visit.

Brand awareness

Brand awareness: the public’s ability to recognise a brand and associate it with an activity or promise.

In practice: Measure recall or branded searches consistently, beyond impressions alone.

Breadcrumb trail

Sequence of links showing a page’s place in the site structure and allowing a return to parent levels.

Reference: W3C WAI : Breadcrumb Pattern

In practice: check that each parent leads to a real, accurately named page.

Breakpoint

A threshold at which layout rules change. Choose it around content needs and test on both sides; it does not identify a particular phone model.

Reference: MDN : Responsive web design · Source consulted 2026-10-18

In practice: add a breakpoint where content stops fitting, then test intermediate widths.

Broken link

Link no longer reaching its intended resource because of an incorrect address, removal or untracked change.

In practice: fix the link at source first and test its final destination.

Browser

Software that requests web resources, interprets their content and presents pages or applications to users. Its engine, settings and extensions can affect observed behavior. A browser differs from a search engine: the former is used to visit the latter, among other services.

Reference: MDN : Browser · Source consulted 2026-10-18

In practice: repeat a task in the audience’s browsers and in a profile without extensions when diagnosing a cause. Record device, version and settings; success on one machine does not describe every context.

Browser cache

Private browser HTTP cache storing certain responses for reuse according to freshness and directives. An older response can be revalidated with the server. It differs from localStorage, IndexedDB and service-worker caches; clearing these stores does not necessarily have the same effect.

Reference: MDN : HTTP caching · Source consulted 2026-10-18

In practice: check behaviour after an update; a file retained too long can leave visitors with an outdated interface.

Brute force

Attack trying many password or key combinations. These attempts do not guarantee access.

Reference: OWASP · Credential Stuffing Prevention · Source consulted 2026-10-31

In practice: Watch repeated failures while keeping account recovery usable.

Byte order mark

Initial sequence that can signal Unicode encoding and, in some encodings, byte order. In UTF-8 it is optional and can disrupt tools that do not expect it.

Reference: Unicode Consortium : UTF and BOM

Source consulted : W3C · 2026-10-17

Test the same file with and without an initial mark and check that the first column name stays identical.