The <feGaussianBlur> SVG filter primitive blurs the input image by the amount specified in stdDeviation, which defines the bell-curve.

The Uint8Array typed array represents an array of 8-bit unsigned integers. The contents are initialized to 0 unless initialization data is explicitly provided. Once established, you can reference elements in the array using the object's methods, or using standard array index syntax (that is, using bracket notation).

The <feImage> SVG filter primitive fetches image data from an external source and provides the pixel data as output (meaning if the external source is an SVG image, it is rasterized.)

A literal character specifies exactly itself to be matched in the input text.

The <line> SVG element is an SVG basic shape used to create a line connecting two points.

The <feSpecularLighting> SVG filter primitive lights a source graphic using the alpha channel as a bump map. The resulting image is an RGBA image based on the light color. The lighting calculation follows the standard specular component of the Phong lighting model. The resulting image depends on the light color, light position and surface geometry of the input bump map. The result of the lighting calculation is added. The filter primitive assumes that the viewer is at infinity in the z direction.

The <feFuncB> SVG filter primitive defines the transfer function for the blue component of the input graphic of its parent <feComponentTransfer> element.

The nullish coalescing assignment (??=) operator, also known as the logical nullish assignment operator, only evaluates the right operand and assigns to the left if the left operand is nullish (null or undefined).

The dur attribute indicates the simple duration of an animation.

Functions are one of the fundamental building blocks in JavaScript. A function in JavaScript is similar to a procedure—a set of statements that performs a task or calculates a value, but for a procedure to qualify as a function, it should take some input and return an output where there is some obvious relationship between the input and the output. To use a function, you must define it somewhere in the scope from which you wish to call it.