rk matters." }, { "id": "disc101", "title": "Discrete Math and Logic", "host": "playa2", "desc": "The mathematics of computing: logic, proof, sets, counting and graphs.", "lessons": ["Propositions and truth tables", "Proof techniques", "Sets and functions", "Counting and combinatorics", "Graphs and networks"], "intro": "Logic studies statements that are either true or false, called propositions, such as 'it is raining' or '7 is prime'. We combine them with connectives: AND (both true), OR (at least one true), NOT (the opposite), and IF-THEN (implication, which is only false when the first part is true and the second false). A truth table lists every combination of truth values and the result, so you can check an argument mechanically. Two statements are logically equivalent when their truth tables match; for example, NOT (A AND B) is equivalent to (NOT A) OR (NOT B), one of De Morgan's laws. These rules are exactly what computer circuits and program conditions are built from." } ] }, { "id": "engineering", "name": "Engineering & Architecture", "host": "solid", "blurb": "Designing and building the world: structures, machines, circuits and the spaces people live in.", "courses": [ { "id": "eng101", "title": "Introduction to Engineering Design", "host": "solid", "desc": "The design process from problem statement to prototype: requirements, constraints, trade-offs and testing.", "lessons": ["What engineers do", "Defining the problem and requirements", "Brainstorming and trade-offs", "Prototyping and testing", "Communicating a design"], "intro": "Engineers apply science and mathematics to design things that solve real problems under real constraints: a bridge that carries traffic safely, a phone battery that lasts all day, a water system for a village. Most engineering work follows a design process: define the problem, research what exists, set requirements and constraints such as budget, safety and materials, generate ideas, choose one by weighing trade-offs, build a prototype, test it, and improve it. The process is a loop, not a straight line, because testing almost always reveals something you missed. Good engineers write things down, measure instead of assuming, and treat a failed test as information." }, { "id": "struct101", "title": "Structures: Forces in Buildings and Bridges", "host": "solid", "desc": "How structures stand up: loads, tension and compression, beams, trusses, arches and safety factors.", "lessons": ["Loads and forces", "Tension and compression", "Beams and bending", "Trusses and triangles", "Arches, domes and cables", "Safety factors and failure"], "intro": "Every structure is a path that carries loads safely down to the ground. Dead loads are the permanent weight of the structure itself; live loads are the changing weight of people, furniture, vehicles or snow; and environmental loads include wind and earthquakes. For a structure to stand still, the forces on it must balance: everything pushing down must be matched by supports pushing up, and the turning effects, called moments, must cancel too. Engineers draw free-body diagrams, simple sketches showing every force acting on a part, to check that balance. If you can follow the load path from a roof to the foundations, you understand the heart of structural engineering." }, { "id": "arch101", "title": "Architecture: Space, Form and Light", "host": "playa2", "desc": "Reading and designing buildings: scale, circulation, light, materials and the history of architectural ideas.", "lessons": ["Firmness, commodity and delight", "Scale and proportion", "Circulation and plans", "Light and materials", "Cities and public space"], "intro": "Around 2,000 years ago the Roman architect Vitruvius wrote that a good building needs three qualities, usually translated as firmness, commodity and delight. Firmness means it stands up and lasts; commodity means it works well for the people who use it; delight means it moves or pleases the people who experience it. Architects still use this triad to judge designs. Architecture is communicated mainly through drawings: the plan is a horizontal cut seen from above, the section is a vertical cut, and the elevation shows a face of the building. Learning to read these drawings, and to imagine walking through them, is the first skill of the course." }, { "id": "elec101", "title": "Electronics: Circuits from Scratch", "host": "solid", "desc": "Voltage, current and resistance, Ohm's law, simple circuits and the building blocks of digital electronics.", "lessons": ["Charge, voltage and current", "Ohm's law and resistors", "Series and parallel circuits", "Capacitors and timing", "From transistors to logic gates"], "intro": "Electric current is the flow of electric charge,