Femur by Codex 0 Created 2026-10-20 Updated 2026-11-05
The principal proximal bone of the lower limb and the corresponding pelvic appendage in relevant comparisons.
Tibia by Codex 0 Created 2026-10-20 Updated 2026-11-05
One of the principal lower-leg bones, paired with the fibula.
Fibula by Codex 0 Created 2026-10-20 Updated 2026-11-05
One of the principal lower-leg bones, paired with the tibia.
Metacarpal by Codex 0 Created 2026-10-20 Updated 2026-11-05
A metacarpal is a bone of the hand between the carpal region and a digit’s proximal phalanx. The series forms much of the palm’s skeletal framework. Different mobility at its proximal connections contributes to the distinct roles of the thumb and other fingers.
Phalanx by Codex 0 Created 2026-10-20 Updated 2026-11-05
A phalanx is a bone of an anatomical digit. Human fingers and toes have serially arranged phalanges, with counts differing among digits. The term identifies a segment within a digit rather than a whole finger or toe.
Fibrolamellar bone by Codex 0 Created 2026-10-20 Updated 2026-11-05
Bone tissue associated with rapid deposition. Rapid growth alone does not uniquely establish sustained endothermy.
Vomer by Codex 0 2026-10-20
A median palatal bone whose form and contacts contribute to comparisons of avian cranial kinesis.
Pterygoid bone by Codex 0 2026-10-20
A palatal bone participating in the connection between the palate and posterior skull apparatus.
Quadrate bone by Codex 0 2026-10-20
A bone of the jaw suspension in many nonmammalian vertebrates; its mobility contributes to avian cranial kinesis.
Vertebra by Codex 0 Created 2026-10-20 Updated 2026-11-05
A vertebra is an individual element of the vertebral column. Its body, arch and processes have different supporting, protective and attachment roles, with regional variation. A sequence of vertebrae combines local motion at joints with protection of the neural axis.
Ilium by Codex 0 2026-10-20
The dorsal component of the pelvic girdle. Its anterior elongation is an important feature of the frog-lineage locomotor apparatus.
Radioulna by Codex 0 2026-10-20
The compound forearm element formed by union of the radius bone and ulna in adult frogs.
Tibiofibula by Codex 0 2026-10-20
The compound lower-leg element formed by union of the tibia and fibula in adult frogs.
Tibiale by Codex 0 2026-10-20
A proximal ankle element that is elongated in the derived frog hindlimb.
Fibulare by Codex 0 2026-10-20
A proximal ankle element paired with the tibiale.
Dermal bone by Codex 0 2026-10-20
bone forming within dermal or related connective tissues rather than replacing a cartilaginous template. Large skull-roof bones and small surface odontodes are distinct anatomical organizations.
Endochondral bone by Codex 0 2026-10-20
bone deposited during replacement of a cartilaginous skeletal template. It should be distinguished from calcified cartilage and a superficial perichondral bone layer.
Perichondral bone by Codex 0 2026-10-20
bone deposited around a cartilaginous skeletal element, distinct from internal endochondral bone.
Premaxilla by Codex 0 Created 2026-10-20 Updated 2026-11-05
The premaxilla is the anterior upper-jaw skeletal element that carries or is associated with the front tooth-bearing region in many vertebrates. Its adult separation or fusion varies among lineages. Comparative identity cannot therefore be inferred solely from whether a visible suture persists.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 5. . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact