The foundation of modern engineering drawing lies in descriptive geometry, formalized by French mathematician Gaspard Monge in the late 18th century. His work established orthographic projection, allowing 3D objects to be accurately represented on 2D planes.

Today, standardization is governed by organizations such as:

• ISO (International Organization for Standardization): Global standards for line types, symbols, and projections (primarily First Angle).
• ANSI (American National Standards Institute) / ASME (American Society of Mechanical Engineers): Standards widely used in the US, Canada, and the Philippines (primarily Third Angle).

• T-Square: Used for drawing horizontal lines and providing a straight edge for set squares. It slides vertically along the left edge of the drafting board.
• Set Squares (Triangles): Used for drawing vertical and inclined lines. Standard angles are 30°-60°-90° and 45°-45°-90°. They can be combined to create angles in 15° increments.
• Drawing Media: Modern manual drafting uses specific media types: Vellum (translucent, durable paper), Tracing Paper (economical, temporary), and Mylar (polyester film, extreme durability, and dimensional stability).
• Drafting Pencils: Pencil cores are graded by hardness. Hard (4H-9H) are for initial light layouts; Medium (3H-B), especially H and HB, are for general line work and lettering; Soft (2B-7B) are for artistic shading, not typical technical drawing.
• Compass: Used for drawing circles and arcs of specific radii.
• Protractor: Used for measuring and laying out angles not covered by set squares.
• Scale Rule (Architect's or Engineer's Scale): Used to measure and lay out precise lengths at specific reduction or enlargement ratios (e.g., 1:100, 1:50).
• French Curves / Flexible Curves: Used to draw irregular, non-circular curves (e.g., parabolas, ellipses) by connecting plotted points.
• Drafting Tape/Dots: Used to secure the paper to the board without tearing it upon removal.

• Visible Line (Object Line): A thick, continuous line (typically 0.5mm - 0.7mm). Represents visible edges, outlines, and contours of the object.
• Hidden Line: A thin, dashed line (typically 0.3mm). Represents edges or contours hidden from the current view. Dashes should be uniform (approx. 3mm) with very small gaps (1mm).
• Center Line: A thin line consisting of alternating long and short dashes. Indicates axes of symmetry, centers of circles, or paths of motion.
• Dimension Line: A thin line terminated with arrowheads at both ends. Indicates the extent and direction of a dimension. A gap is typically left in the middle for the dimension text.
• Extension Line: A thin, continuous line extending outward from the object to the dimension line. A small visible gap (approx. 1-2mm) must exist between the object outline and the start of the extension line.
• Section Line (Hatching): Thin, continuous lines drawn at an angle (usually 45°). Indicates surfaces that have been cut by a cutting plane in a sectional view.
• Cutting Plane Line: A thick line (often phantom style or dashed) with arrows at the ends indicating the direction of sight for a sectional view.
• Phantom Line: A thin line of long dashes followed by two short dashes. Shows alternate positions of moving parts, adjacent features, or repeated details.
• Break Line: Used to shorten the view of a long object with a uniform cross-section. Can be a thick zig-zag (long break) or a thin freehand wavy line (short break).

• Gothic Lettering: Single-stroke, sans-serif letters are the universal standard (similar to Arial or Helvetica).
• Uppercase Usage: Virtually all notes, titles, and dimensions should be written in UPPERCASE letters to maximize clarity.
• Orientation: Letters can be vertical or inclined (usually at a 67.5° angle). Vertical lettering is highly preferred in modern CAD-generated drawings.
• Height Standards: Minimum heights ensure readability after printing and scaling: Titles (5mm - 7mm), Subtitles (3mm - 5mm), General Notes and Dimensions (minimum 3mm).
• Guidelines: In manual drafting, extremely light, parallel horizontal guidelines are always drawn first to ensure uniform letter height.

• Borders: Margins are required around the drawing area. Often, the left margin is wider (e.g., 20mm or 25mm) to allow for binding a set of plans, while the top, bottom, and right margins are narrower (e.g., 10mm).
• Title Block Location: Generally located in the bottom-right corner of the sheet.
• Zoning/Grid System: Large sheets (like A0 or A1) may have numbers along one edge and letters along the adjacent edge (like a map) to allow quick referencing of specific details (e.g., "See Detail at C-4").