H.264, 268, 269

• video, 270

Hadoop, 1003–1004, 1004f

Halftones, 241

• vs. pixels, 241f

Hardware architect, 33

Hash functions, 850, 850f

• MD5, 851t

• rainbow tables, 852f

• using slow, 853–854

Hash table data structure, 732

Head and body, 85–87

Headers, 61–62, 103–104

• cells, connection, 217c

• example, 105f

• textual description, 216

• working with HTTP, 671

Headings, 87–91

• addition, 192f

Headless CMS, 973

HEAD request, 63

height attribute (HTML), 195

height property (CSS), limitations, 162f

Hibernate, 764

Hickson, Ian, 79

Hidden content, 951

Hidden links, 952

High-availability, 815, 815f

Higher-order functions, 593

Hosting

• cloud hosting, 899

• collocated hosting, 898–899

• companies, 36

• dedicated hosting, 898

• hardware, 898

• in-house hosting, 898–899

• sharing, 895–898

Hosts, 50–51

• header, 61

Hot-linking, 921

Hover effect, 198f

HSB color model, 247

htaccess, 922–923

HTTP Basic Authentication, 826–827, 826f

HTTPS downgrade attack, 848f

HTTP Token Authentication, 829–830

Hue Saturation Lightness (HSL) color model, 247

• example, 247f

Human–Computer interaction (HCI), 34

Hyperlinks, query strings (usage), 659–660

Hypertext Markup Language (HTML), 7, 78–79

• attributes, 79

• canvas, 273

  • element, 273

• date/time controls, 214t

• definition, 74–79

• divisions, 89

• documents

  • outline, 81f

  • presentation, 123

  • structure, 84–87

• DOM Element Properties, 425t

• editor, 111

• elements, 79, 87–101

  • nesting, 80–81, 81f

  • parts, 80f

• form

  • data flow, 654f

  • example, 456c

• form, sample, 200f

• form-related HTML elements, 204, 204t

• headings, 87–91

• links, 92

• paragraphs, 91

• PHP

  • combination, 621c

• presentation markup, 81

• semantic markup, 81–83

• structure, visualization, 82f

• syntax, 79–81

• usage of emojis, 99

• validators, 77, 78f

• XHTML, 76–78

• version 5 (HTML), 78–79

  • articles, 106, 107f

  • asides, 108–109

  • browser validation, 227f

  • details and summary, 109, 110f

  • div-based XHTML layout, 102f

  • documents, 84f, 88f, 90f

  • figures/captions, 106–108

  • head and body, 85–87

  • headers/footers, 103–104

  • main, 105–106

  • navigation, 104–105

  • sections, 106, 107f

  • semantic elements, additional, 110–111

  • semantic structure elements, 102–115, 104f

  • structure elements, 84f

  • validation, 227–228

• version 5.1 (HTML), 79

  • details and summary, 109, 110f

Hypertext Transfer Protocol (HTTP), 7, 48, 60–64

• caching, 923

• constraints, 781

• Cross-origin resource sharing (CORS), 510

• headers, 61–62, 202, 505f

• illustration, 60f

• normal HTTP request—response loop, 501f

• request, 62

  • methods, 62–63

• request–response loop, 501f

• response codes, 64, 64t

• variables, 202

Hypertext Transfer Protocol Secure (HTTPS), 840–848

• Certificate Authorities (CA), 842–845, 843f

• domain-validated certificates, 843–844

• downgrade attack, 848f

• extended-validation certificates, 845

• free certificates, 845

• handshake, 842f

• migrating to, 846–848

• organization-validated certificates, 844–845

• Secure Socket Layer (SSL), 840

• self-signed certificates, 846

• Transport Layer Security (TLS), 840

• usage, 841f

Hypervisors, 900–901, 901f