BSEB Inter Multimedia & Web Tech flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Multimedia definition

Integrated delivery of text, graphics, audio, video and animation in one interactive system. When elements are linked non-linearly it becomes hypermedia.

Nyquist sampling rule

The sample rate must be greater than twice the highest frequency in the signal. Otherwise aliasing occurs and the original waveform cannot be reconstructed.

Raster versus vector

Raster stores a color value per pixel and pixelates when enlarged. Vector stores geometric primitives with attributes and scales without loss of quality.

Authoring tool metaphors

Card or page based (screens in sequence), icon or event based (flowchart), time based (timeline with layers), and web based (HTML, CSS, JavaScript editing).

Point and pica

A point is 1/72 of an inch and a pica is 12 points. These units are used for type size, leading and print measurement.

Kerning versus tracking

Kerning adjusts spacing between one specific pair of characters. Tracking adjusts uniform spacing across an entire run of characters or a block.

Additive versus subtractive color

RGB is additive and applies to emitted light on screens. CMYK is subtractive and applies to reflected light from ink on paper.

Effective PPI

Image pixel width divided by printed width in inches. A 1200-pixel image printed 6 inches wide yields 200 pixels per inch.

Bit depth and dynamic range

Each additional bit of audio resolution adds roughly 6 dB of dynamic range. 16-bit gives about 96 dB and 24-bit about 144 dB.

Lossy versus lossless audio

Lossless codecs such as FLAC reconstruct exact samples. Lossy codecs such as MP3 and AAC discard masked detail and cannot restore the original.

Container versus codec

A container such as MP4 or MKV holds tracks, metadata and timing. A codec such as H.264 or VP9 defines how the compressed data is encoded.

Chroma subsampling

Color information is stored at lower resolution than brightness, for example 4:2:0. This reduces bitrate because human vision resolves color less sharply.

Keyframe and tweening

Keyframes mark defined poses or states. Tweening automatically generates the in-between frames, and easing shapes acceleration at the start and end.

Onion skinning

A technique that displays previous and next frames faintly behind the current one so the animator can align successive drawings accurately.

Squash and stretch

An animation principle where objects deform under force while preserving apparent volume, conveying weight, flexibility and impact to the viewer.

Stop-motion animation

Physical objects or figures are photographed one frame at a time with small movements between shots, then played back to create apparent motion.

Semantic HTML landmarks

Elements such as header, nav, main, article, section, aside and footer describe page regions, helping assistive technology and search engines interpret structure.

Void HTML elements

Elements with no content or closing tag, including img, br, hr, input, meta and link. They carry all information in attributes.

HTML table structure

Data tables use caption, thead, tbody and th cells with scope attributes. Tables are not used for page layout in modern practice.

CSS box model

Each element is a box of content, padding, border and margin. With border-box sizing, the declared width includes padding and border.

CSS specificity order

Inline styles outrank IDs, which outrank classes, attributes and pseudo-classes, which outrank elements. Later equal-specificity rules override earlier ones.

WCAG POUR principles

Content must be Perceivable, Operable, Understandable and Robust. Conformance levels are A, AA and AAA, with AA the common legal target.

Contrast ratio AA

Normal text needs at least 4.5:1 contrast against its background. Large text of 18 pt or 14 pt bold needs at least 3:1.

let, const and var

let and const are block-scoped, with const preventing reassignment. var is function-scoped and hoisted, which often causes unexpected behavior.

Strict versus loose equality

The === operator compares value and type without coercion. The == operator coerces types first, so '1' == 1 is true while '1' === 1 is false.

Client-side validation limits

Browser validation improves user experience but can be bypassed or disabled. Servers must repeat all validation and authorization checks independently.

Cross-site scripting defense

Escape or encode output, prefer textContent over innerHTML, validate input and apply a Content Security Policy to limit injected script execution.

TCP versus UDP

TCP is connection-oriented with handshake, ordering and retransmission. UDP is connectionless with less overhead, suited to streaming and DNS lookups.

DNS record types

A maps a name to IPv4, AAAA to IPv6, CNAME creates an alias, MX routes mail and TXT holds verification or policy text.

URL components

A URL contains scheme, host, optional port, path, optional query string and optional fragment. The fragment stays in the browser and is never sent to the server.

Storyboard versus wireframe

A storyboard sequences scenes, visuals, audio and interaction over time. A wireframe shows layout and content hierarchy without visual styling.

Creative Commons licensing

Standard licenses that vary by attribution, commercial use, derivative permission and share-alike terms. Each combination states exactly what reuse is allowed.