Rabin-Karp: Searching With Rolling Fingerprints
Most string searches work by comparing letters. Rabin-Karp takes a different road: it boils every chunk of text down to a single number, a fingerprint, and compares the numbers instead.…
How Ctrl+F Finds Text Instantly: KMP and String Matching Explained
You press Ctrl+F, type a word, and every match on a long page lights up before you have lifted your finger. It feels like magic, but the problem underneath is…
Data Types Explained: Integers, Floats, Booleans and Why They Differ
Every beginner hits the same wall sooner or later. They add 0.1 and 0.2, get 0.30000000000000004, and decide the computer is broken. It is not broken. It is doing exactly…
How a Phone’s Contact Search Finds Matches as You Type
You type the letter “m” and Mom appears. You add an “a” and the list shrinks. By the third letter, the person you wanted is already on screen and you…
Top 20 Networking Interview Questions with Plain-English Answers
I have sat on both sides of the interview table for a long time, and I can tell you something that surprises most candidates: interviewers rarely want a textbook definition.…
What Is a Port Number? Why 80, 443 and 22 Matter
Networking basics · TCP and UDP · Security An IP address gets data to the right computer. But that computer is running dozens of programs at once: a browser, a…
What Is DHCP? How Your Device Gets an IP Address Automatically
You walk into a café, tap the Wi-Fi name, and within a second the web works. Nobody typed an address, picked a gateway or told your phone where to find…
Heap vs Sorted Array for Priority Handling
Data structures · Priority queues · Performance An emergency room does not treat patients in the order they walk in. A nurse looks at each person and the sickest one…
LRU Cache: Build One With a Hash Map and a Linked List
Your phone keeps the apps you used recently and quietly drops the ones you have ignored. Your browser, your database and your CPU do the same thing with data. The…
Git and GitHub Explained for Beginners (With Real Examples)
Version control · Beginner guide · Hands-on If you have ever saved a file as report_final_v2_REAL_final.docx, you already understand why Git exists. It is the grown-up version of that habit:…