500 Generalities
 

• 500 Natural sciences & mathematics 
  • 500.2 Physical sciences
  • 500.5 Space sciences
  • 500.8 History and description with respect to kinds of persons
• 501 Philosophy & theory
• 502 Miscellany 
  • 502.8 Auxiliary techniques and procedures; apparatus, equipment, materials
• 503 Dictionaries & encyclopedias
• 504 
• 505 Serial publications
• 506 Organizations & management
• 507 Education, research, related topics 
  • 507.8 Use of apparatus and equipment in study and teaching
• 508 Natural history 
  • 508.3 Treatment by areas, regions, places in general; by specific continents, countries, localities in the ancient world
• 509 Historical, areas, persons treatment

• 510 Mathematics 
  • 510.1 Philosophy and theory
• 511 General topics 
  • 511.3 Mathematical (Symbolic) logic
• 512 Algebra & number theory 
  • 512.9 Foundations of algebra
  • 513 Arithmetic
  • 513.2 Specific arithmetic operations
  • 513.5 Numeration systems
• 514 Topology
• 515 Analysis
• 516 Geometry 
  • 516.2 Euclidean geometry
  • 516.3 Analytic geometries
  • 516.9 Non-Euclidean geometries
• 517
• 518
• 519 Probabilities & applied mathematics 
  • 519.2 Probabilities
    519.3 Game theory
    519.4 Applied numerical analysis
    519.5 Statistical mathematics
    519.7 Programming
    519.8 Special topics

• 520 Astronomy & allied sciences 
  • 520.1 Philosophy and theory
• 521 Celestial mechanics
• 522 Techniques, equipment, materials
• 523 Specific celestial bodies & phenomena 
  • 523.1 The universe; space, galaxies, quasars
  • 523.2 Solar system
  • 523.3 Moon
  • 523.4 Planets
  • 523.5 Meteoroids, solar wind, zodiacal light
  • 523.6 Comets
  • 523.7 Sun
  • 523.8 Stars
  • 523.9 Satellites and rings; eclipses, transits, occultations
• 524 
• 525 Earth (Astronomical geography)
• 526 Mathematical geography 
  • 526.3 Geodetic surveying
  • 526.9 Surveying
• 527 Celestial navigation
• 528 Ephemerides
• 529 Chronology

• 530 Physics 
  • 530.1 Theories and mathematical physics
  • 530.4 States of matter
  • 530.8 Testing and measurement
• 531 Classical mechanics; Solid mechanics
• 532 Fluid mechanics; Liquid mechanics
• 533 Gas mechanics
• 534 Sound & related vibrations 
  • 534.5 Subsonic and ultrasonic vibrations
• 535 Light & related radiations 
  • 535.5 Beams
  • 535.6 Color
  • 535.8 Spectroscopy
• 536 Heat
• 537 Electriticy & electronics 
  • 537.5 Electronics
  • 537.6 Electric currents (Electrodynamics) and thermoelectricity
• 538 Magnetism
• 539 Modern physics 
  • 539.2 Radiations (Radiant energy)
  • 539.7 Atomic and nuclear physics

• 540 Chemistry & allied sciences 
  • 540.1 Philosophy and theory
  • 540.2 Miscellany
• 541 Physical & theoretical chemistry 
  • 541.2 Theoretical chemistry
  • 541.3 Physical chemistry
• 542 Techniques, equipment, materials
• 543 Analytical chemistry
• 544 Qualitative analysis
• 545 Quantitative analysis
• 546 Inorganic chemistry
• 547 Organic chemistry 
  • 547.1 Physical and theoretical organic chemistry
  • 547.3 Analytical organic chemistry
  • 547.7 Macromolecular and related compounds
  • 547.8 Other organic substances
• 548 Crystallography
• 549 Mineralogy 
  • 549.9 Geographic distribution of minerals

• 550 Earth sciences 
  • 550.1 Philosophy and theory
  • 550.9 Historical, geographic, persons treatment
• 551 Geology, hydrology, meteorology 
  • 551.1 Gross structure and properties of the earth
  • 551.2 Volcanoes, earthquakes, thermal waters and gases
  • 551.3 Surface and exogenous processes and their agents
  • 551.4 Geomorphology and hydrosphere, water
  • 551.5 Meteorology
  • 551.6 Climatology and weather
  • 551.7 Historical geology
  • 551.8 Structural geology
  • 551.9 Geochemistry
• 552 Petrology
• 553 Economic geology 
  • 553.2 Carbonaceous materials
  • 553.3 Iron
  • 553.4 Metals and semimetals
  • 553.5 Structural and sculptural stone
  • 553.6 Other economic materials
  • 553.7 Water
  • 553.8 Gems
• 554 Earth sciences of Europe
• 555 Earth sciences of Asia
• 556 Earth sciences of Africa
• 557 Earth sciences of North America
• 558 Earth sciences of South America
• 559 Earth sciences of other areas

• 560 Paleontology; Paleozoology 
  • 560.9 Historical, geographic, persons treatment of paleontology, of paleozoology
• 561 Paleobotany
• 562 Fossil invertebrates
• 563 Fossil primitive phyla
• 564 Fossil mollusks & related phyla
• 565 Other fossil invertebrates
• 566 Fossil vertebrates
• 567 Fossil cold-blooded vertebrates 
  • 567.9 Reptiles
• 568 Fossil birds
• 569 Fossil mammals

• 570 Life sciences
• 571 
• 572 Human races 
  • 572.9 Geographic distribution of races
• 573 Physical anthropology 
  • 573.2 Evolution and genetics of humankind
  • 573.3 Prehistoric humankind
• 574 Biology 
  • 574.1 Physiology
  • 574.2 Pathology
  • 574.3 Development and maturation
  • 574.4 Anatomy and morphology
  • 574.5 Ecology
  • 574.6 Economic biology
  • 574.8 Tissue, cellular, molecular biology
  • 574.9 Geographic treatment of organisms
• 575 Evolution & genetics 
  • 575.1 Genetics
  • 575.2 Variation
• 576 Microbiology
• 577 General nature of life
• 578 Microscopy in biology
• 579 Collection and preservation

• 580 Botanical sciences
• 581 Botany 
  • 581.1 Physiology of plants
  • 581.2 Pathology of plants
  • 581.3 Development and maturation of plants
  • 581.4 Anatomy and morphology
  • 581.5 Ecology
  • 581.6 Economic botany
  • 581.8 Tissue, cellular, molecular botany
  • 581.9 Geographic treatment of plants
• 582 Seed-bearing plants 
  • 582.1 Nontaxonomic groupings
• 583 Dicotyledons
• 584 Monocotyledons
• 585 Gymnosperms (Naked-seed plants)
• 586 Seedless plants
• 587 Pteridophyta (Vascular seedless plants)
• 588 Bryophytes
• 589 Thallophytes & prokaryotes 
  • 589.1 Lichens
  • 589.2 Fungi
  • 589.3 Algae
  • 589.4 Specific types of algae
  • 589.9 Prokaryotes; Bacteria

• 590 Zoological sciences
• 591 Zoology 
  • 591.1 Physiology of animals
  • 591.2 Pathology of animals
  • 591.3 Development and maturation of animals
  • 591.4 Anatomy and morphology of animals
  • 591.5 Ecology of animals
  • 591.4 Anatomy and morphology
  • 591.5 Ecology
  • 591.6 Economic biology
  • 591.8 Tissue, cellular, molecular zoology
  • 591.9 Geographic treatment of animals
• 592 Invertebrates
• 593 Protozoa, Echinodermata, related phyla 
  • 593.1 Protozoa
  • 593.4 Parazoa Sponges
  • 593.6 Anthozoa
  • 593.7 Hydrozoa and Scyphozoa
  • 593.8 Comb jellies
  • 593.9 Echinodermata
• 594 Mollusks & related phyla
• 595 Other invertebrates 
  • 595.1 Worms and related animals
  • 595.3 Crustaceans and chelicerates
  • 595.4 Arachnids
  • 595.6 Progoneata
  • 595.7 Insects
• 596 Vertebrates
• 597 Cold-blooded vertebrates 
  • 597.6 Amphibians
  • 597.7 Apoda (Caecilians)
  • 597.8 Anura (Salientia)
  • 597.9 Reptiles
• 598 Birds 
  • 598.2 Ecology and geographic treatment of birds
  • 598.3 Charadriiformes, Ciconiiformes, Gruiformes
  • 598.4 Anseriformes and other water birds
  • 598.5 Palaeognathae
  • 598.6 Galliformes and Columbiformes
  • 598.7 Coliiformes, Cuculiformes, Piciformes, Psittaciformes, Trogoniformes
  • 598.8 Perching birds, Apodiformes, Coraciiformes
  • 598.9 Birds of prey, owls, Caprimulgiformes
• 599 Mammals 
  • 599.1 Monotremes
  • 599.2 Marsupials
  • 599.3 Unguiculata
  • 599.4 Bats
  • 599.5 Cetaceans and sirenians
  • 599.6 Paenungulata
  • 599.7 Ungulates, carnivores, aardvarks
  • 599.8 Primates
  • 599.9 Humankind and forebears