Networking / RFC Delimiting "one message" in TCP: Trying length prefixes on localhost
We test a length prefix, which adds a 4-byte length to the TCP byte stream so the receiving side can determine message boundaries.
Networking / RFC 
Linux / CLI / DevOps What is the difference between symbolic links and hard links? — Understanding through inodes
Create two types of links in a temporary directory and understand their differences based on inodes and behavior after deleting the original file.
PowerShell How Many Threads Are in a Process? — Observing Reality with PowerShell
Read the current PowerShell process and observe how multiple threads exist within a single PID.
PowerShell Base64 Is Not Encryption: Visually Confirming Reversibility with PowerShell
Encode and decode Base64 in PowerShell to visually understand the difference between encoding and encryption.
Programming / Web Development Understanding through Manga! Trying Out a Page-Switching Manga Viewer with Image Data: Landscape 4-Page Version and Smartphone Vertical-Scrolling Version
Using 4 Papanda manga images and JSON, we compare mechanisms by creating a landscape viewer that switches back and forth using JavaScript and a vertical-reading version for smartphones that stacks the same images vertically.
Microsoft 365 / Azure Cannot Verify Registered TXT Record in Microsoft 365: Troubleshooting DNS, TTL, and Authoritative Servers with PowerShell
When Microsoft 365 TXT verification fails, systematically troubleshoot authoritative DNS, recursive DNS, TTL, and configuration values using PowerShell.
PowerShell Observing Win32 Window Handles with PowerShell
Read MainWindowHandle of a GUI process from PowerShell and observe the Win32 HWND.
Networking / RFC Observing that TCP lacks message boundaries on localhost
Safely observe how the number of sends and the boundaries of receives do not match in TCP transmission and reception on localhost.
PowerShell Inspecting PowerShell for Dangerous Paths and Oversized Extractions Before Expanding ZIP Files
Before expanding a ZIP file, use PowerShell to inspect paths that extend outside the destination directory, total size, file count, and unexpected extensions.
Linux / CLI / DevOps Changing umask on Ubuntu and verifying how new file permissions change
Compare umask 022 and 077 in a temporary directory and observe how new file permissions are determined.