The file that decides more about your site than any plugin, and the one most people copy from a tutorial once and never open again. These articles go through the constants that matter and the ones that quietly do nothing.
Security & Privacy
WordPress File Permissions: 644, 755 and When Something Else
chmod 777 makes the error disappear by handing write access to every process on the server. What the three digits mean, the standard WordPress set, and why ownership decides which digit even gets read.
Error Establishing a Database Connection: What WordPress Is Actually Telling You
The message means PHP ran, wp-config.php was read, and the connection to MySQL failed. Nothing more. Here is how to tell a wrong password from a downed server from a host that ran out of connections, and what to do about each.
Allowed Memory Size Exhausted: Where the WordPress Memory Limit Lives
The "Allowed memory size exhausted" fatal error involves three separate ceilings, and the one most people raise is not the one that stopped the request. How PHP's memory_limit, WP_MEMORY_LIMIT and WP_MAX_MEMORY_LIMIT interact, and why images trigger the error more often than anything else.
ü is not corruption. It is one umlaut, two UTF-8 bytes, read by a program that believed they were Windows-1252, then saved again so the wrong reading became the content. Here is how to tell which wrong turn your text took, why copied replacement lists only half work, and what to check in the database before you clean anything.
wp-config.php Explained: The Constants That Earn Their Place
wp-config.php is the first file WordPress reads that is specific to your install, and almost every fix you will ever be handed ends with "add this line to wp-config.php". Here is what the file actually does, which constants earn their place, and why the placement rule matters.
Cron Expression Generator: The Five Fields and the OR Rule
The five cron fields, the four special characters, and the rule that catches everyone: day of month and day of week are combined with OR, not AND. Plus why WP-Cron misses schedules, and the two lines that put WordPress on a real timer.
A white screen with no error message isn't a WordPress bug. It's PHP dying silently mid-request. Here's how to see the real error in minutes and the exact order to check plugins, theme, and memory limits.
The WordPress Uploads Folder, and How to Move It Safely
The year and month structure under wp-content/uploads comes from one boolean option, and the full path is recomputed on every request rather than stored. That is why repointing the folder is trivial and why moving the files is not.
WordPress Salts and Passwords: The Eight Lines Nobody Rotates
The eight define() lines in wp-config.php sign every admin cookie and every nonce your site issues. What each one does, why Math.random cannot be trusted to make them, what actually breaks when you rotate them, and an offline generator for the replacements.
WordPress Images Not Showing: Five Layers, Five Fixes
A broken image icon is not one problem. It is the same symptom produced by five different failures at five points in the request, and the fix for one does nothing for the other four. Read the server response first, then work down the layers with read-only commands.
