The do...while statement creates a loop that executes a specified statement as long as the test condition evaluates to true. The condition is evaluated after executing the statement, resulting in the specified statement executing at least once.

The intercept attribute defines the intercept of the linear function of color component transfers when the type attribute is set to linear.

The spreadMethod attribute determines how a shape is filled beyond the defined edges of a gradient.

The repeatDur attribute specifies the total duration for repeating an animation.

The pointsAtY attribute represents the y location in the coordinate system established by attribute primitiveUnits on the <filter> element of the point at which the light source is pointing.

Classes are a template for creating objects. They encapsulate data with code to work on that data. Classes in JS are built on prototypes but also have some syntax and semantics that are unique to classes.

The repeatCount attribute indicates the number of times an animation will take place.

The if...else statement executes a statement if a specified condition is truthy. If the condition is falsy, another statement in the optional else clause will be executed.

The textLength attribute, available on SVG <text> and <tspan> elements, lets you specify the width of the space into which the text will draw. The user agent will ensure that the text does not extend farther than that distance, using the method or methods specified by the lengthAdjust attribute. By default, only the spacing between characters is adjusted, but the glyph size can also be adjusted if you change lengthAdjust.

A unicode character class escape is a kind of character class escape that matches a set of characters specified by a Unicode property. It's only supported in Unicode-aware mode. When the v flag is enabled, it can also be used to match finite-length strings.