Where do I put my WordPress code? Functions php file or Plugins

In this video, we answer the question, "Where should I put my code I copied from another source in WordPress"

Learn why you should use plugins or functions.php in 3 mins.

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How to use WordPress Gutenberg Block Editor
== WordPress 5.4 Gutenberg Blocks Updates - https://www.youtube.com/playlist?list=PLNqG1qGUllk0lI2Omhvp54Qn9-MIEhQzX
== WordPress Gutenberg blocks for Designers - https://www.youtube.com/playlist?list=PLNqG1qGUllk3DY91Bq_26L8meIXM_Uo4E
== Gutenberg WordPress Block Editor tutorials for beginners - https://www.youtube.com/playlist?list=PLNqG1qGUllk2xOKt79aI12GgX2DX0aNx-

WordPress Plugin Development from Scratch
== Build Most Popular & Most Commented Post Plugin - https://www.youtube.com/playlist?list=PLNqG1qGUllk05gUz_VB5nCHEN9A3OpS94
== Build SMS Plugin with External WordPress API Integration using custom WordPress Databases - https://www.youtube.com/playlist?list=PLNqG1qGUllk0NSTrNF2xa1zHNzMi3M7su
== WordPress External APIs Integration Plugin Development - https://www.youtube.com/playlist?list=PLNqG1qGUllk0U2-5ZBNxSNxQrPO-4CqnR

Convert WordPress to mobile App in Headless WordPress
== Convert WordPress Sports Website into Mobile Application - https://www.youtube.com/playlist?list=PLNqG1qGUllk3qMrJcXUeP1Ge5U4fKtAR
== Make GraphQL API endpoints with WordPress Headless CMS WPGraphQL Plugin - https://www.youtube.com/playlist?list=PLNqG1qGUllk03llIgPYGVTwY14lAPDkBp

WooCommerce E-Commerce customizations
== Build Free Custom E-commerce Online Shop using WooCommerce - https://www.youtube.com/playlist?list=PLNqG1qGUllk2qFmbexV2SikF8bXqvDW-H

Customize Your WordPress & ClassicPress
== Build Custom REST API Endpoints with WordPress or ClassicPress - https://www.youtube.com/playlist?list=PLNqG1qGUllk06KZP9N1nRG-FpnTr_TD9u
== Custom Dashboard Widgets - https://www.youtube.com/playlist?list=PLNqG1qGUllk2h51557gV74x8p1RrlEmah
== Build Custom Admin - https://www.youtube.com/playlist?list=PLNqG1qGUllk1M5L8Xo-K1g6B3OrkliKDs

Learn Git
== Git tutorial for writers + software developers for beginners - https://www.youtube.com/playlist?list=PLNqG1qGUllk2PnSJiUw1SCjiS6pNhIR2f