0_what_is_javascript
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What is Javascript?
Node Tree
- javascript
Nodes
javascript | |
content | JavaScript |
children | API, QuerySelectorAll, addEventListener, builds_on_html_css, client_side, comments, dynamic, event_listener, exec_environment, implement_complex_features_on_web, inline_js_handlers, interpretted, multiline, tag_script, uses_script_tag |
implement_complex_features_on_web | |
content | Scripting/programming language that allows you to implement complex features on web pages |
children | complex_feature_ex (examples of "complex features") |
parents | javascript |
complex_feature_ex | |
content | Create dynamically udpating content, control multimedia, animate images |
parents | implement_complex_features_on_web |
builds_on_html_css | |
content | Buils on top of HTML, CSS |
parents | javascript |
API | |
content | Application Programming Interface (API) |
children | browser_API, ready_made_set_code_building_blocks (description), third_party_API |
parents | javascript |
ready_made_set_code_building_blocks | |
content | ready-made set of code building blocks that allow a dev to implement programs otherwise hard or impossible |
parents | API |
browser_API | |
content | Browser APIs |
children | AV_APIs, DOM_API, canvas_webgl, geolocation |
parents | API |
DOM_API | |
content | DOM API |
parents | browser_API |
geolocation | |
content | Geolocation |
parents | browser_API |
canvas_webgl | |
content | Canvas / WebGL |
parents | browser_API |
AV_APIs | |
content | AV APIs HTMLMediaElement and WebRTC |
parents | browser_API |
third_party_API | |
content | Third-Party APIs |
children | google_maps, grab_code_info_somewhere, twitter |
parents | API |
content | |
parents | third_party_API |
google_maps | |
content | Google Maps |
parents | third_party_API |
grab_code_info_somewhere | |
content | Generally have to grab code and info somewhere on the web. |
parents | third_party_API |
exec_environment | |
content | Execution environment |
children | bucket_for_running_code, code_run_separately |
parents | javascript |
bucket_for_running_code | |
content | Each browser tab has its own bucket for running code in |
parents | exec_environment |
code_run_separately | |
content | Code is run separately |
parents | exec_environment |
interpretted | |
content | Interpretted |
children | compiled (versus), just_in_time_compiling |
parents | javascript |
compiled | |
content | Compiled |
parents | interpretted |
just_in_time_compiling | |
content | Most modern JS interpreters use a technique called just-in-time compiling to improve performance |
parents | interpretted |
client_side | |
content | Client-side |
children | run_on_users_computer, server_side (versus) |
parents | javascript |
server_side | |
content | Server-sisde |
children | server_side_languages |
parents | client_side |
run_on_users_computer | |
content | Run on Users Computer |
parents | client_side |
server_side_languages | |
content | PHP, Python, Ruby, ASP.NET, Javascript (via node.js) |
parents | server_side |
dynamic | |
content | Dynamic |
children | ability_to_update_page (description), static_code (versus) |
parents | javascript |
static_code | |
content | Static code |
parents | dynamic |
ability_to_update_page | |
content | Ability to udpate display of web page / app to show different things in different circumstances |
parents | dynamic |
uses_script_tag | |
content | Uses <script> |
children | external, internal |
parents | tag_script, javascript |
internal | |
content | internal |
children | external (versus) |
parents | uses_script_tag |
external | |
content | external |
parents | internal, uses_script_tag |
inline_js_handlers | |
content | Inline JS handlers |
parents | javascript |
remarks | bad practice to use these |
QuerySelectorAll | |
content | QuerySelectorAll() |
parents | addEventListener, javascript |
addEventListener | |
content | addEventListener() |
children | DOMContentLoaded, QuerySelectorAll |
parents | event_listener, javascript |
event_listener | |
content | Event Listener |
children | addEventListener |
parents | javascript |
DOMContentLoaded | |
content | DOMContentLoaded |
children | HTML_body_parsed |
parents | addEventListener |
tag_script | |
content | <script> |
children | defer, uses_script_tag |
parents | javascript |
defer | |
content | defer |
children | HTML_body_parsed (modern approach), async |
parents | tag_script |
HTML_body_parsed | |
content | Signifies HTML body is parsed |
parents | defer, DOMContentLoaded |
async | |
content | async vs |
children | download_noblock, load_background_ASAP (when to use) |
parents | defer |
load_background_ASAP | |
content | Should be used to load in place background scripts as soon as possible |
parents | async |
no_guarantee_order | |
content | no guarantee on execution order |
parents | blocks_page |
blocks_page | |
content | Blocks page when executing |
children | no_guarantee_order |
parents | download_noblock |
download_noblock | |
content | Downloads without blocking |
children | blocks_page |
parents | async |
comments | |
content | comments |
children | single_line |
parents | javascript |
single_line | |
content | Single Line (//) |
parents | comments |
multiline | |
content | multiline (/* */) |
parents | javascript |