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Expandable. Referring to hardware or software, the term is a popular buzzword in the IT world. A "highly scalable" device or application implies that it can handle a large increase in users, workload or transactions without undue strain.

There May Be a Price
Scalable does not always mean that expansion is free. Extra-cost hardware or software may indeed be required to handle more work. Nevertheless, scalability is a positive feature of a product that is sold to fast-growing companies, because it implies that growth can be accommodated without having to make major changes or learn new procedures. See scale.


(1) To resize a device, object or system. With regard to increases, "scale vertically" or "scale up" refers to expanding a single machine's capability. To "scale horizontally" or "scale out" refers to adding more machines.

With regard to decreases, the term is often used with cutting-edge chip technologies. For example, "this memory scales with CMOS" means that the memory architecture takes advantage of the increasing miniaturization in CMOS chip fabrication by becoming smaller as well. See at scale, upconvert and scalable.

(2) To increase. The term is widely used to refer to expanding a system, quite often a website or Web-based application that is quickly gaining popularity. See at scale, blitzscaling, scalable and scaler.

(3) To move with. The phrase "the image scales with the window" means that as an on-screen window is dragged by the user to a larger or smaller frame size, the image inside continuously expands or contracts to fit the changing frame.

(4) To change the representation of a quantity in order to bring it into prescribed limits of another range. For example, values such as 1249, 876, 523, -101 and -234 might need to be scaled into a range from -5 to +5.

(5) To designate the position of the decimal point in a fixed or floating point number.

(6) To increase or decrease the size of a digital image.

(7) A large size. For example, the "efficiencies of scale" means the economies derived from expansion.

Scaling Up and Down
Enlarging an image adds pixels, and quality software can produce a decent result for small increases. However, no matter how good the algorithms, a large increase softens the new image. In addition, the original sharpness cannot be brought back as this pixel example shows. See dithering.

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Before/After Your Search Term
Sbusscalable coding
SC Cardscalable font
SC connectorscalable video coding
SCAscalar processing
SCADAscalar processor
SCADA attackscalar variable
Scalascale horizontally
scalabilityscale out

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