#IT Knowledge
63 posts
How 1Password and Google Password Manager Stay Safe: Master Passwords and Encryption
How password managers protect dozens or hundreds of passwords — explained without code. How one master password locks the rest, how zero-knowledge sync hides the vault from the company, why auto-fill quietly defeats phishing, and how the field is shifting toward passkeys.
What's the Difference Between 5G, LTE, and Wi-Fi? The Roads Your Phone Takes to the Internet
The 5G, LTE, and Wi-Fi indicators on your phone status bar are different roads to the internet. Cell towers and licensed spectrum, what improves with each generation, why 5G rarely feels as fast as advertised, and the moments your phone switches roads — all explained for non-developers.
How Are YouTube and Netflix Recommendations Decided? An Introduction to Recommender Systems
This post explains, without any code, how YouTube's next video and Netflix's home screen get tuned to your taste. It covers collaborative filtering that follows similar people, the content-based approach that looks at similarity between items, and limits like the filter bubble, at a non-developer's level.
How Does Find My Locate a Phone That's Turned Off? The Offline Finding Network
A phone with no internet and no power still shows up on the map. The secret is the Find My network, which turns hundreds of millions of strangers' devices into anonymous relays. This post covers Bluetooth signals, end-to-end encryption, AirTag, and anti-stalking protections.
Why Ads Follow You: Cookies, RTB, and Privacy
Why the running shoes you glanced at follow you across every news site — explained without code. What ad networks collect through cookies and device IDs, how the 0.2-second real-time bidding auction works, and what users can still do as third-party cookies fade and Apple ATT changes the rules.
How Do Siri and Alexa Understand What I Say? From Speech to Text
The claim that voice assistants are always listening is only half true. This post follows the relay from the small ear that waits only for a wake word, through speech recognition that turns sound into text, to reading intent and composing an answer. It also explains why they sometimes mishear you, and what the privacy picture actually looks like.
How Zoom and Google Meet Actually Work: Real-Time Communication and WebRTC
How video conferencing captures, compresses, and delivers audio and video without noticeable delay — explained without code. What WebRTC is, why direct browser-to-browser calls still need signaling, STUN, TURN, and SFU servers, and how the structure changes as meetings grow, all at a level a non-developer can follow.
How Backups Actually Stay Safe: The 3-2-1 Rule
What a backup really is, how it differs from sync, and why the 3-2-1 rule became the standard — explained without code. From external drives and NAS to cloud backup, automation, and restore tests, all at a level a non-developer can follow.
How Do Google Drive and iCloud Stay in Sync? Cloud Storage and Conflict Copies
What actually happens while a photo taken on your phone shows up on your laptop. Change detection, uploading only the modified pieces, the conflicted copy that appears when two devices edit the same file, and why sync is not a backup — explained for non-developers.
How Do Messaging Apps Deliver Your Messages? Servers and End-to-End Encryption
Your message doesn't fly straight to the other person's phone. This post explains the store-then-deliver structure behind messaging apps, how read receipts work, the difference between encryption in transit and end-to-end encryption, and why some apps keep a separate secret chat mode, all at a non-developer's level.
How Do You Analyze Product Data and Logs? Tracking Basics for PMs and Marketers
This post explains, without any code, how the data and logs a service leaves behind pile up, and how they turn into metrics and analysis. It covers the difference between logs, events, and metrics, plus funnel analysis and how to spot vanity metrics, at a PM and marketer's level.
How Does Home Wi-Fi Work? Routers, Public vs Private IP, 2.4GHz and 5GHz
Your home has one internet line, yet your phone, laptop, and TV are all online at once — the secret is the router. Public vs private IP addresses, how NAT works, the difference between 2.4GHz and 5GHz, and what your Wi-Fi password actually does, explained for non-developers.