SSE

SSE is an acronym used in several domains, notably in web technologies, computing, statistics, and industry. The most common interpretations include Server-Sent Events, Streaming SIMD Extensions, Sum of Squared Errors, and the British energy company Scottish and Southern Energy plc.

Server-Sent Events (SSE) is a web technology for receiving automatic updates from a server over HTTP. The client opens a persistent, unidirectional connection via an EventSource interface, while the server pushes messages as text/event-stream. Each event can include an id, an event name, and data, with the connection automatically reestablishing if it drops. SSE is commonly used for real-time feeds and notifications, and contrasts with WebSockets by providing server-to-client communication only.

Streaming SIMD Extensions (SSE) are a family of x86 processor instructions that enable parallel processing of multiple data points with 128-bit registers. Introduced by Intel in 1999, SSE includes revisions such as SSE, SSE2, SSE3, SSSE3, SSE4.1, and SSE4.2. They accelerate multimedia, graphics, and vector computations and are supported by most modern CPUs from Intel and AMD; newer instruction sets such as AVX have largely superseded them, though many applications still rely on SSE.

Sum of Squared Errors (SSE) is a statistic measuring the discrepancy between observed values and those predicted by a model. It is computed as the sum of squared residuals and is the objective function minimized in ordinary least squares regression. SSE helps assess model fit alongside metrics like R-squared and informs parameter estimation in predictive models.

Scottish and Southern Energy plc, commonly shortened to SSE, is a British energy company involved in electricity generation, transmission, distribution, and gas supply. The company operates in the United Kingdom and Ireland and has been a prominent provider within the energy market.