{ "@context": "https://schema.org", "@type": "Dataset", "name": "WiredSimple system cards", "description": "Every WiredSimple explainer reduced to its system card: inputs, outputs, components, failure modes and real-world examples.", "url": "https://www.wiredsimple.com/system-cards.json", "license": "https://creativecommons.org/licenses/by/4.0/", "creator": { "@type": "Organization", "name": "WiredSimple", "url": "https://www.wiredsimple.com/" }, "dateModified": "2026-08-20", "measurementTechnique": "Hand-authored per article and validated against the schema in src/content.config.ts.", "cards": [ { "id": "tech/how-bluetooth-works", "title": "How Bluetooth Works: The Invisible Cable Replacement", "url": "https://www.wiredsimple.com/tech/how-bluetooth-works/", "category": "tech", "subcategory": "networking", "shortAnswer": "Bluetooth is a short-range radio system in the crowded 2.4 GHz band. To survive the interference, paired devices hop between 79 channels up to 1,600 times a second, following the same pseudo-random sequence so they stay in step. Any interfering signal disrupts only a fraction of a second before the connection moves elsewhere.", "region": "global", "inputs": [ "Digital data from a source device", "Radio frequency energy (2.4 GHz band)", "Pairing and authentication credentials", "User intent (connection request)" ], "outputs": [ "Wirelessly transmitted data (audio, files, control signals)", "Device discovery and pairing information", "Acknowledgement and error-correction signals", "Low-energy sensor and beacon data" ], "components": [ "Frequency-hopping spread spectrum (FHSS) engine", "Adaptive power control", "Piconet controller (master/peripheral architecture)", "Protocol stack (L2CAP, RFCOMM, SDP, profiles)", "Pairing and encryption manager", "Low Energy (LE) advertising subsystem" ], "failureModes": [ "Interference from other 2.4 GHz devices (Wi-Fi, microwaves)", "Pairing failures from mismatched protocols or full device lists", "Audio latency and codec degradation under weak signal", "Range dropouts caused by physical obstacles or body absorption", "Security exploits (BlueBorne, KNOB attack) from unpatched firmware" ], "examples": [ "Wireless earbuds streaming audio from a phone", "Fitness tracker syncing heart-rate data to an app", "Car infotainment system handling hands-free calls", "Bluetooth mesh network controlling smart lighting", "AirDrop-style file transfer between nearby laptops" ] }, { "id": "money/what-is-a-pension", "title": "What is a Pension and How Does It Work?", "url": "https://www.wiredsimple.com/money/what-is-a-pension/", "category": "money", "subcategory": "investing", "shortAnswer": "A pension is a long-term investment pot for retirement, made powerful by two things: government tax relief that boosts every contribution, and decades of compound growth. In a defined contribution scheme you build a pot you later draw down; in a defined benefit scheme your employer guarantees an income for life. Starting early matters far more than contributing more.", "region": "uk", "inputs": [ "Employee contributions (% of salary)", "Employer contributions (matched)", "Government tax relief", "Investment returns over time" ], "outputs": [ "Pension pot at retirement", "Regular income in retirement", "Tax-free lump sum (25% in UK)" ], "components": [ "Defined contribution (DC) pot", "Defined benefit (DB) scheme", "State pension entitlement", "Compound growth over decades", "Pension provider / trustee" ], "failureModes": [ "Employer insolvency (DB schemes)", "Poor investment fund choice", "Early withdrawal penalties", "Missing auto-enrolment opt-in", "Forgetting old workplace pensions" ], "examples": [ "Workplace auto-enrolment pension", "NHS / Teachers final-salary pension", "Self-employed SIPP", "State pension at 67", "Pension consolidation" ] }, { "id": "science/why-is-the-sky-blue", "title": "Why is the Sky Blue?", "url": "https://www.wiredsimple.com/science/why-is-the-sky-blue/", "category": "science", "subcategory": "physics", "shortAnswer": "The sky is blue because of Rayleigh scattering. Air molecules scatter short wavelengths far more strongly than long ones — blue light is scattered roughly 5.5 times more than red — so blue light bounces around the atmosphere and reaches your eye from every direction. At sunset the light travels through much more air, scattering the blue away and leaving red.", "region": "global", "inputs": [ "White sunlight (all visible wavelengths)", "Nitrogen and oxygen molecules (N₂, O₂)", "Viewing angle relative to sun" ], "outputs": [ "Blue scattered light (day sky)", "Red/orange direct light (sunsets)", "Black sky (no atmosphere = space)" ], "components": [ "Photons of visible light", "Atmospheric molecules", "Rayleigh scattering mechanism", "Wavelength-dependent scattering (λ⁻⁴)", "Human eye's colour sensitivity" ], "failureModes": [ "Clouds (Mie scattering = white)", "Pollution/dust (redder sky)", "Volcanic ash (vivid sunsets)", "Smoke (orange/red tint)", "Twilight arch (purple/indigo)" ], "examples": [ "Blue daytime sky", "Red/orange sunsets", "White clouds", "Pink sunrise", "Deep blue sky at altitude" ] }, { "id": "money/how-mortgages-work", "title": "How Mortgages Work", "url": "https://www.wiredsimple.com/money/how-mortgages-work/", "category": "money", "subcategory": "banking", "shortAnswer": "A mortgage is a loan secured against a property: if you stop paying, the lender can repossess and sell it. Each monthly payment splits between interest, which is the lender's fee, and capital, which reduces your debt. Early on almost all of it is interest; only in the later years does most of it start reducing what you owe. That schedule is called amortisation.", "region": "uk", "inputs": [ "Property purchase price", "Deposit amount", "Interest rate (fixed or variable)", "Mortgage term (years)" ], "outputs": [ "Monthly payment (capital + interest)", "Legal ownership of the property", "LTV ratio (risk assessment)" ], "components": [ "Loan-to-value ratio (LTV)", "Amortisation schedule", "Lender's valuation", "Mortgage deal (fixed/tracker/SVR)", "Solicitor / conveyancer" ], "failureModes": [ "Interest rate rise (variable mortgage)", "Negative equity (house price falls)", "Missed payment (repossession risk)", "Failed valuation survey", "Gazumping before exchange" ], "examples": [ "First-time buyer in UK", "Remortgaging to a better rate", "Buy-to-let investment purchase", "Using Help to Buy scheme", "Releasing equity in retirement" ] }, { "id": "science/how-do-batteries-work", "title": "How Batteries Work", "url": "https://www.wiredsimple.com/science/how-do-batteries-work/", "category": "science", "subcategory": "physics", "shortAnswer": "A battery converts chemical energy into electrical energy through a controlled reaction. Two electrodes sit in an electrolyte that lets ions pass but blocks electrons, so the electrons are forced to travel through your device instead — and that flow is the current. Batteries degrade because the reaction is never perfectly reversible.", "region": "global", "inputs": [ "Chemical energy (stored in electrodes)", "Electrical current (during charging)", "Lithium ions (Li⁺)" ], "outputs": [ "Electrical current (during discharge)", "Heat (as waste)", "Depleted electrodes" ], "components": [ "Anode (graphite / silicon)", "Cathode (lithium metal oxide)", "Electrolyte (ion transport medium)", "Separator (prevents short circuit)", "Battery management system (BMS)" ], "failureModes": [ "Lithium plating (dendrite growth)", "Electrolyte decomposition", "Thermal runaway (fire risk)", "Cathode cracking (mechanical)", "Capacity fade over cycles" ], "examples": [ "Smartphone battery", "EV battery pack (Tesla, etc.)", "AA alkaline battery", "Laptop battery", "Grid-scale energy storage" ] }, { "id": "tech/how-ssds-work", "title": "How SSDs Work: Flash Storage Explained", "url": "https://www.wiredsimple.com/tech/how-ssds-work/", "category": "tech", "subcategory": "hardware", "shortAnswer": "An SSD stores data by trapping electrons in insulated floating-gate transistors, where they stay without power. Reading measures whether a cell holds charge; writing forces electrons through an insulating oxide layer. That oxide degrades slightly on every write, which is why SSDs have a finite endurance and a controller spreads writes evenly across all cells.", "region": "global", "inputs": [ "Electrical charge (program/erase)", "NVMe / SATA commands", "Controller firmware" ], "outputs": [ "Stored bits in floating-gate cells", "Fast read/write access", "Persistent data (no power needed)" ], "components": [ "NAND flash cells", "Floating-gate transistor", "SSD controller chip", "DRAM cache (on-drive)", "Wear-levelling algorithm" ], "failureModes": [ "Electron tunnel oxide wear", "Write endurance exhaustion (TBW)", "Controller failure", "Power loss during write", "Extreme temperature exposure" ], "examples": [ "OS boot drive", "Gaming fast load times", "MacBook internal storage", "USB flash drives", "Camera memory cards" ] }, { "id": "money/how-credit-scores-work", "title": "How Credit Scores Work", "url": "https://www.wiredsimple.com/money/how-credit-scores-work/", "category": "money", "subcategory": "credit", "shortAnswer": "A credit score is a statistical prediction of how likely you are to miss a debt payment in the next two years. Lenders report your account history to credit bureaus, and a scoring model weighs five factors: payment history, amounts owed, length of history, new applications and credit mix. Payment history and credit utilisation carry the most weight.", "region": "global", "inputs": [ "Payment history (on-time vs missed)", "Total debt owed", "Length of credit history", "New credit applications", "Credit mix (types of accounts)" ], "outputs": [ "FICO score (300–850)", "Vantage score (300–850)", "Risk category (poor to exceptional)" ], "components": [ "Credit bureaus (Equifax, Experian, TransUnion)", "FICO scoring model", "Credit utilisation ratio", "Hard vs soft enquiries", "Public records (CCJs, bankruptcies)" ], "failureModes": [ "Missed payment (stays 7 years)", "Maxing out credit cards", "Closing old accounts", "Too many hard enquiries", "Identity theft / fraud" ], "examples": [ "Getting a mortgage at a good rate", "Approved for a car finance deal", "Phone contract without upfront cost", "Renting a flat without a guarantor", "Balance transfer credit card" ] }, { "id": "tech/what-is-ram", "title": "What is RAM and Why Does It Matter?", "url": "https://www.wiredsimple.com/tech/what-is-ram/", "category": "tech", "subcategory": "hardware", "shortAnswer": "RAM is your computer's short-term working memory. Each bit is stored as an electrical charge in a tiny capacitor, which leaks and must be refreshed thousands of times per second — which is why RAM forgets everything when power is lost. It is far faster than an SSD, so the CPU keeps the data it is actively using there. More RAM helps only until your workload fits.", "region": "global", "inputs": [ "Electrical charge (capacitor)", "Clock signal from CPU", "Memory controller commands" ], "outputs": [ "Data bits (0 or 1)", "Fast temporary storage", "Working space for active apps" ], "components": [ "DRAM capacitor cells", "Transistor gate (access)", "Row/column address decoder", "Memory controller (CPU)", "Memory bus (data pathway)" ], "failureModes": [ "Capacitor charge leak (bit flip)", "Overheating (thermal throttle)", "Incompatible XMP profile", "Incorrect DIMM slot pairing", "ESD damage during install" ], "examples": [ "Keeping 20 browser tabs open", "Running Photoshop + Slack", "Gaming while streaming", "Video editing timeline cache", "Virtual machine workloads" ] }, { "id": "science/how-vaccines-work", "title": "How Vaccines Work", "url": "https://www.wiredsimple.com/science/how-vaccines-work/", "category": "science", "subcategory": "biology", "shortAnswer": "A vaccine trains your immune system to recognise a pathogen without you having to catch it. It introduces an antigen — a distinctive molecular shape from the pathogen's surface — so your body mounts a full immune response and then stores it as memory cells. If the real pathogen arrives later, those memory cells recognise it and destroy it before it can make you seriously ill.", "region": "global", "inputs": [ "Antigen (viral protein or weakened pathogen)", "Adjuvant (immune alarm signal)", "Healthy immune system" ], "outputs": [ "Memory B cells (antibody production)", "Memory T cells (cell-mediated immunity)", "Specific antibodies (neutralising)", "Herd immunity (population level)" ], "components": [ "Antigen (target for immune learning)", "Dendritic cells (antigen presenters)", "B lymphocytes (antibody factories)", "T lymphocytes (cell killers + helpers)", "Memory cells (long-term immunity)" ], "failureModes": [ "Immune evasion by mutating virus", "Waning antibody levels over time", "Immunocompromised recipient", "Incorrect cold-chain storage", "Rare allergic reaction (anaphylaxis)" ], "examples": [ "MMR vaccine (measles, mumps, rubella)", "COVID-19 mRNA vaccines", "Annual flu jab", "Childhood DTP schedule", "HPV vaccine" ] }, { "id": "tech/how-wifi-works", "title": "How Wi-Fi Works", "url": "https://www.wiredsimple.com/tech/how-wifi-works/", "category": "tech", "subcategory": "networking", "shortAnswer": "Wi-Fi works by converting internet data into radio waves. Your router takes the digital data arriving over your broadband line and encodes it onto radio signals at 2.4 GHz or 5 GHz, varying the wave's phase and amplitude to represent bits. Your device's wireless adapter picks up those waves and decodes them back into data, with WPA3 encrypting everything in transit.", "region": "global", "inputs": [ "Internet data (TCP/IP packets)", "Mains power", "Router firmware" ], "outputs": [ "Radio waves (2.4 GHz or 5 GHz)", "Decoded data on your device", "IP address assignment (DHCP)" ], "components": [ "Router / access point", "Wireless NIC (adapter)", "Radio transmitter & antenna", "OFDM modulator", "WPA3 encryption layer" ], "failureModes": [ "Interference (microwaves, Bluetooth)", "Channel congestion (neighbours)", "Physical obstruction (concrete walls)", "Wrong Wi-Fi password", "ISP outage upstream" ], "examples": [ "Streaming Netflix in 4K", "Video calls on a laptop", "Smart home sensors", "Airport public Wi-Fi", "Wireless printers" ] } ] }