"In geometry, a line is an infinitely long object with no width, depth, or curvature."
The path created by a moving point. It can be straight, curved, thick, thin, smooth, or rough.
Shape: The two-dimensional area that is defined by a boundary.
Size: The physical dimensions of a shape, either in relation to other shapes in the composition.
Direction: The orientation or angle of a line or shape in relation to the frame or other elements in the composition.
Texture: The quality of a surface, such as its smoothness, roughness, or patterned appearance.
Value: The range of lightness or darkness in a composition.
Color: The hue, saturation, and value of a color.
Contrast: The difference in appearance or character between two or more elements in the composition.
Balance: The distribution of visual weight or symmetry in the composition.
Unity: The sense of oneness, harmony, or coherence in the composition.
Emphasis: The use of contrast, color, size, or other visual elements to draw attention to a particular part of the composition.
Vertical line: A straight line that runs vertically from top to bottom.
Horizontal line: A straight line that runs horizontally from left to right.
Diagonal line: A line that slopes at an angle between horizontal and vertical.
Curved line: A line that is not straight, but curves in one or more places.
Zigzag line: A line that changes direction repeatedly, creating a series of peaks and valleys.
Wavy line: A line that curves in a gentle, wave-like pattern.
Broken line: A line that is interrupted or not continuous, consisting of small segments or dots.
Outlining line: A line that defines the boundaries of a shape or form.
Contour line: A line that follows the curves and contours of an object or figure, creating a sense of volume and depth.
Implied line: A line that is suggested or implied but not actually drawn, created through the placement of shapes, colors, or other elements in a composition.
Dotted line: A line made up of evenly spaced dots.
Textured line: A line that has a rough or bumpy surface, created through the use of materials such as pastels or charcoal.
Thick line: A line that is wider and bolder than a normal line, creating a greater sense of weight and emphasis.
Thin line: A line that is narrow and delicate, used to create a sense of lightness or subtlety.
Gestural line: A line that is loose and expressive, capturing the movement and energy of the artist's hand.
"Thus, lines are one-dimensional objects..."
"...though they may exist embedded in two, three, or higher dimensional spaces."
"The word line may also refer to a line segment in everyday life that has two points to denote its ends (endpoints)."
"A line can be referred to by two points that lie on it..."
"...or by a single letter."
"Euclid described a line as a 'breadthless length' that 'lies evenly with respect to the points on itself'."
"...he introduced several postulates as basic unprovable properties from which he constructed all of geometry."
"Euclidean line and Euclidean geometry are terms introduced to avoid confusion with generalizations introduced since the end of the 19th century, such as non-Euclidean, projective, and affine geometry."
"Infinity length, no width, no depth, no curvature."
"...embedded in two, three, or higher dimensional spaces."
"A line segment has two points to denote its ends (endpoints)."
"A line can be referred to by two points that lie on it."
"Euclid described a line as a 'breadthless length'."
"...to construct all of geometry."
"...such as non-Euclidean, projective, and affine geometry."
"...an infinitely long object with no width, depth, or curvature."
"...though they may exist embedded in two, three, or higher dimensional spaces."
"The word line may also refer to a line segment..."
"A line can be referred to... by a single letter."