Fabric.js, 273

Facebook (FB)

• FBML, usage, 962

• integrated Facebook web game, illustration, 969f

• Like social plugin, screenshot, 962f

• newsfeed

  • generation, 963f

  • items, plugins (relationship), 961f

• Open Graph Debugger, 965f

• pages, screenshots, 959f

• register, 961–962

• social plugins, 960–961

Facebook Markup Language (XFBML), 960

• version, 963

Failover clustering on master, 769, 770f

Failover redundancy, 19

Falsy values, 371–372

Favicon, 266

FBML, usage, 963

fetch(), 503, 743

• adding loading animation, 512, 513f

• common mistakes with, 508, 508f

• HTTP Methods, 510–512

• multiple, 508

  • example, 509c

• parallel invocations, 520f

• vs.performance of localStorage, 527c

• via POST example, 511f, 511–512c

• with useEffect(), 584c

fetch command (git), 233

Fiber optic cable, 26

Fields, 721

<fieldset> element, 217

<figcaption> element, 109f

<figure> element, 108

Figures

• captions, 106–108

• elements, 109f

Files

• checking out, 232–233

• committing, 231

• formats, 258–267

• merge, 233

• ownership management, 913

• requests, responding to, 917

File Transfer Protocol (FTP), 48, 60

File upload

• control (Chrome), 211f

• size, limitation

  • PHP, usage, 566c

FileZilla, 48

filter(), 482–483

Filters, 324

• action, 325f

• using, 324c

find(), 482

FireBug, 68

First Contentful Paint (FCP), 66

First Meaningful Paint (FMP), 66

First Paint (FP), 66

Flexbox, 292–297

• compared to grid, 292f

• container, 293, 295f

• item, 293, 296f

• layout, 292

• usage, 279–283, 280f

• use cases, 294

Floats

• elements, 283–284

• property, 283

Flow analysis, 999

focus event, 458

• responding to, 457f

fontawesome.com, 211, 458

Font family, 165–167

• differences, 167f

• sizes, 167–171

• specification, 166f

• stack, 167. See also Web fonts, stack

• weight, 171–172

Foreign keys, 722

• link tables, 723f

Forking (git), 234

for loop, 373–374, 623

• example (JavaScript), 373f

• example (PHP), 639c

• foreach (PHP), 639c

• forEach() function (JavaScript), 481, 482f

• for. . .in (JavaScript), 374

• for. . .of (JavaScript), 378

• iterating an array (JavaScript), 378

• iterating an array (PHP), 639c

Form-based authentication, 827–829, 828f

FormData

• form element, 202

Forms, 199–203

• accessibility, 215–218

• basic HTML form, 456c

• changes events, responding to, 458

• choice controls, 205–209

• control elements, 204–215

• controlled components (React), 568–569

• data flow(React), 570, 571f, 573c, 574f

• data, sending, 202

• elements, query string data (relationship), 202f

• events, 450, 450t, 458

• form element, 202–203

  • designing, 220–221, 221f

  • styling, 219–220, 219f

• function, 200–201

  • illustration, 201f

• JavaScript, 456–463

• labels, 220f

• movement events, responding to, 458

• PHP, 655, 658, 654f, 656f

• React, 568

• structure, 199–200

• styling and designing, 218–221

• submission, 462–463

• uncontrolled components (React), 569–570

• validation, 458–462

Four-layer network model, 43, 44f

Fragment, 59–60

• tag anchor, 60

Frame events, 451, 451t

• lazy loading via, 452f

Frameworks

• JavaScript front-end, 546–550

• need of, 546–547

Full-duplex communication, 696

Full IDEs, 113, 114f

Functional components(React), 555–556

• using hooks, 567f

Functional composition, 593

Functional testing, 884

Function constructors (JavaScript), 397–398

• defining and using, 398c

• example, 398f

• inefficient (sample), 486c

Function declarations, 388

• destroying, 409c

Function expression, 389

Functions (JavaScript), 388–402

• anonymous, 389

• callback, 394–395, 394f

• closures, 408, 411f

• constructors, 397–398

• declarations, 388

• default parameters, 390

• defined, 388

• expressions, 389

• hoisting, 392, 393f

• nested, 391–392, 392c

• scope, 403–405, 406f, 409f, 410f

• with objects, 396–397

• without return value, 388c

Functions (PHP), 627–634

• definition, return value (absence), 628c

• example, 627c

• global scope, 633

• interface, 647

• invoking, 628

• overloading, 629

• parameters, 629–634

• scope, 632–634

• syntax, 627–628

• usage, 632–634

Functions-as-a-Service (FaaS), 705–706, 706f