The Cheeger constant, also known as the Cheeger function or Cheeger number, is a concept from graph theory and geometric analysis that provides a measure of how "well-connected" a graph or a manifold is. In the context of a graph, the Cheeger constant is used to characterize the minimum cut that can be made to partition the graph into two disjoint sets.
In graph theory, the concept of "cutwidth" pertains to a way of measuring the layout of a graph. More formally, the cutwidth of a graph is defined with respect to a linear ordering of its vertices. ### Definition Given a graph \( G \) and a linear ordering (or layout) of its vertices, the cutwidth measures the maximum number of edges that cross any vertical "cut" when the vertices are arranged in a row according to the specified order.
The Hyper-Wiener index is a graph invariant used in the study of chemical graph theory, where it is often applied to describe the structural properties of molecules. Specifically, it captures information about the connectivity and topology of a molecular graph. The Hyper-Wiener index \( W^h(G) \) for a graph \( G \) is defined based on the distances between pairs of vertices in the graph.
The Kelmans–Seymour conjecture is a conjecture in graph theory that relates to the structure of certain types of graphs. Specifically, it deals with the behavior of complete graphs and the existence of specific subgraphs within them. Formulated by Paul Kelmans and Neil Seymour, the conjecture states that every 2-edge-connected graph can be represented as a graph obtained from a complete graph by the contraction of edges.
A Partial k-tree is a data structure used primarily in the field of combinatorial optimization and computer science, particularly in topics related to the representation of combinatorial objects or configurations, such as combinations, subsets, or sequences. In general, a k-tree is a tree structure that represents all possible configurations of k elements chosen from a larger set, and it can be used for various applications, including generating combinations or permutations.
In graph theory, a **Blossom** refers to a specific structure that is relevant in the context of matching algorithms, particularly in the matching of general graphs. The Blossom structure is utilized to handle situations where augmenting paths may be of odd length, which can complicate the process of finding maximum matchings. The concept of Blossoms is associated with the **Edmonds' Blossom Algorithm**, developed by Jack Edmonds in the 1960s.
Univac Text Editor is a software tool developed for text editing on Univac computers, which were among the earliest computer systems used for business and scientific applications. Univac, short for Universal Automatic Computer, was one of the first successful commercial computer brands, developed in the 1950s and 1960s. The Univac Text Editor specifically allowed users to create, modify, and manage text documents on these systems.
In graph theory, a **clique** is a subset of vertices in an undirected graph such that every two distinct vertices in the clique are adjacent. In simpler terms, a clique is a complete subgraph where every vertex is connected to every other vertex. More formally, a clique of size \( k \) is a set of \( k \) vertices such that there are edges between every pair of vertices in that set.
As of my last knowledge update in October 2021, there is no widely recognized figure in web design specifically named Glenn Davis who has achieved significant notoriety. It is possible that Glenn Davis is a professional or designer who has gained prominence or recognition in the web design community after that date, or he may be a less widely known individual in the field.
AltaVista was one of the early search engines on the internet, launched in 1995. It was developed by Digital Equipment Corporation (DEC) and became popular for its fast search capabilities and user-friendly interface. AltaVista was notable for indexing a vast amount of web pages at the time, allowing users to perform keyword searches and providing various features like advanced search options and translation services.
Internet Explorer (IE) is a web browser developed by Microsoft. It was first released in 1995 as part of the add-on package Plus! for Windows 95 and became a core component of the Windows operating system in subsequent versions. Internet Explorer was widely used throughout the late 1990s and early 2000s, reaching a peak market share of over 90%.
David Siegel is a prominent entrepreneur and business executive known for his contributions to the tech industry and his leadership in various companies. He is best recognized as the CEO of **Stack Overflow**, a question-and-answer website for programmers, which he joined in 2019. Under his leadership, Stack Overflow has focused on enhancing its platform to support developers and the programming community more effectively.
Email, short for "electronic mail," is a method of exchanging digital messages between people using electronic devices, typically over the Internet. It allows users to send and receive text messages, documents, images, and other files. Here's a breakdown of its key components and features: 1. **Addressing**: Each email user has a unique email address, usually in the format `username@domain.com`. This address allows messages to be directed to the correct recipient.
The High Performance Computing Act of 1991 is a significant piece of legislation in the United States that aimed to promote research and development in high-performance computing (HPC) technologies. Here are some key points about the act: 1. **Purpose**: The primary goal of the act was to accelerate the development and application of advanced computing technologies to ensure that the United States would maintain its competitive edge in various scientific, engineering, and industrial domains.
The history of email is a fascinating evolution of technology that reflects advances in communication over several decades. Here’s a brief overview of its development: ### 1. **Early Beginnings (1960s)** - **1960s:** The concept of electronic mail began with the development of ARPANET (Advanced Research Projects Agency Network), the precursor to the modern internet.
The history of wikis dates back to the late 20th century and marks a significant evolution in how information is created, shared, and collaboratively edited online. ### 1. Origins in Early 1990s - **Wiki Concept**: The term "wiki" comes from the Hawaiian word “wikiwiki,” meaning “quick.” The concept was developed by Ward Cunningham, who created the first wiki in 1995 called **WikiWikiWeb**.
The Network Startup Resource Center (NSRC) is an organization that provides support for the development and operation of computer networks in developing regions and countries. Established in the mid-1990s and based in the United States, the NSRC aims to assist in the establishment of network infrastructures, primarily in educational institutions and research organizations, to promote access to the Internet and improve connectivity.
The "List of Internet challenges" typically refers to a collection of viral activities or tasks that users participate in or share online, often through social media. These challenges can range from harmless fun to risky or dangerous behaviors. Here are some examples, categorized by their nature: ### Fun and Creative Challenges 1. **Ice Bucket Challenge** - Participants dump a bucket of ice water over themselves to raise awareness for ALS.
MHSnet, or Mental Health Services Network, is a network or system that typically focuses on the delivery of mental health services. It is often used in the context of health care and mental health care integration, aiming to provide comprehensive support and resources for individuals dealing with mental health issues. The specifics of MHSnet may vary depending on the region or organization, as different health systems, community programs, or networks use the term to refer to their mental health service offerings.

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 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . 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.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  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