ECU
An electronic control unit (ECU), also referred to as an engine control module (ECM), is an embedded microprocessor-based system in vehicles that processes sensor inputs to regulate critical functions such as fuel injection, ignition timing, emissions control, and throttle response for optimal engine performance and efficiency.[1][2] Originating from mechanical-hydraulic precursors in the 1930s for aircraft engines, digital ECUs emerged in the automotive sector during the 1970s to address rising emissions standards, with widespread adoption by the 1980s incorporating microprocessors for precise, real-time adjustments via stored algorithms and data tables.[3][4] In contemporary vehicles, ECUs—often numbering dozens or more—interconnect via networks like CAN bus to oversee not only powertrain operations but also safety features, infotainment, and advanced driver-assistance systems, enhancing fuel economy, reducing pollutants, and enabling diagnostics through standardized protocols such as OBD-II.[5] While praised for enabling cleaner and more responsive engines, ECUs have drawn scrutiny for vulnerabilities to software glitches, unauthorized remapping that voids warranties or exacerbates wear, and cybersecurity risks from connected features, underscoring the trade-offs between complexity and reliability in electronic vehicle architecture.[6][7]Economic and Monetary Systems
European Currency Unit
The European Currency Unit (ECU) was a unit of account utilized within the European Monetary System (EMS), functioning as a weighted average of the currencies of participating European Economic Community (EEC) member states to foster exchange rate stability and monetary coordination.[8] Defined by Council Regulation (EEC) No. 3180/78 of 18 December 1978, the ECU replaced the prior European Unit of Account (EUA) and entered into operation on 13 March 1979 alongside the EMS framework.[9][10] Unlike physical currencies, it existed solely as an accounting and settlement mechanism, with its value computed daily based on market exchange rates of the constituent currencies.[11] The ECU's initial composition from 1979 to 1984 comprised fixed quantities of nine EEC currencies, with weights determined by factors including each country's share of intra-EEC trade, gross national product, and monetary reserves.[12]| Currency | Units per ECU | Weight (%) |
|---|---|---|
| Belgian franc | 3.80 | 9.64 |
| Danish krone | 0.217 | 3.09 |
| Deutsche Mark | 0.828 | 33.00 |
| French franc | 1.15 | 19.50 |
| Irish pound | 0.116 | 1.15 |
| Italian lira | 109.00 | 9.50 |
| Luxembourg franc | 0.14 | 0.33 |
| Netherlands guilder | 0.286 | 10.50 |
| British pound | 0.0885 | 13.00 |