Learn IT: using simple language and everyday examples to study.
This article explains how computers store Chinese characters using Unicode and UTF-8, covering the history of encoding chaos, Unicode code points, UTF-8 variable-length encoding rules, a step-by-step example of encoding '中', common mojibake causes, BOM, and programming best practices like using utf8mb4 in MySQL.
This article explains ASCII encoding, the standard that maps 128 characters to numbers 0-127, detailing control codes, printable characters, extended ASCII, programming applications like character comparison and case conversion, and why ASCII's English-only limitation led to Unicode.
This article explains computer storage units from bits to petabytes, clarifies the binary (1024) vs decimal (1000) discrepancy causing drives to appear smaller, provides real-world capacity examples, file size references, and practical storage recommendations for phones and computers.
This tutorial teaches bidirectional decimal-binary conversion using division-by-2 remainder method for integers, weight expansion for binary-to-decimal, a subtraction-based shortcut, multiply-by-2 for fractions, plus a power-of-2 reference table and highest-bit estimation technique.
This article explains why computers use binary (0 and 1) instead of decimal, covering the physical reliability of two voltage states, binary counting and conversion methods, how all data types are represented as bit sequences, and the role of Boolean logic and hexadecimal shorthand in computing.
This article explains why computers generate heat, details CPU temperature thresholds and throttling behavior, compares air and liquid cooler types, covers case airflow design including positive and negative pressure, addresses laptop cooling challenges, and provides actionable maintenance steps like dust cleaning, thermal paste replacement, and airflow improvements.
This guide explains how to select a computer power supply by covering wattage calculation, 80 PLUS efficiency ratings, modular cable designs, connector types, form factors, and brand selection criteria to ensure stable hardware operation.
This article explains graphics card fundamentals, covering GPU architecture differences from CPUs, key components like VRAM and cooling, integrated vs discrete GPUs, the five-step rendering pipeline, frame rate targets, resolution impact, ray tracing technology, and non-gaming uses such as video editing and AI training.
This article explains the motherboard's role as the central circuit board connecting all computer components, detailing key parts like CPU sockets, memory slots, chipsets, PCIe and M.2 interfaces, form factors (ATX, mATX, ITX), bus communication, and selection criteria for compatibility and performance.
This article explains the fundamental differences between RAM and hard drives, using analogies like a desk versus a bookshelf to illustrate how RAM provides fast temporary workspace for the CPU while hard drives offer permanent but slower storage, covering HDD vs. SSD, virtual memory, and why insufficient RAM causes system slowdowns.
