PrivacyPrivacy (UK, US) is the ability of an individual or group to seclude themselves or information about themselves, and thereby express themselves selectively. The domain of privacy partially overlaps with security, which can include the concepts of appropriate use and protection of information. Privacy may also take the form of bodily integrity. There have been many different conceptions of privacy throughout history. Most cultures recognize the right of an individual to withhold aspects of their personal lives from public record.
End-to-end encryptionEnd-to-end encryption (E2EE) is a private communication system in which only communicating users can participate. As such, no one, including the communication system provider, telecom providers, Internet providers or malicious actors, can access the cryptographic keys needed to converse. End-to-end encryption is intended to prevent data being read or secretly modified, other than by the true sender and recipient(s). The messages are encrypted by the sender but the third party does not have a means to decrypt them, and stores them encrypted.
Matching (graph theory)In the mathematical discipline of graph theory, a matching or independent edge set in an undirected graph is a set of edges without common vertices. In other words, a subset of the edges is a matching if each vertex appears in at most one edge of that matching. Finding a matching in a bipartite graph can be treated as a network flow problem. Given a graph G = (V, E), a matching M in G is a set of pairwise non-adjacent edges, none of which are loops; that is, no two edges share common vertices.
Email encryptionEmail encryption is encryption of email messages to protect the content from being read by entities other than the intended recipients. Email encryption may also include authentication. Email is prone to the disclosure of information. Most emails are encrypted during transmission, but they are stored in clear text, making them readable by third parties such as email providers. By default, popular email services such as Gmail and Outlook do not enable end-to-end encryption.
Maximum cardinality matchingMaximum cardinality matching is a fundamental problem in graph theory. We are given a graph G, and the goal is to find a matching containing as many edges as possible; that is, a maximum cardinality subset of the edges such that each vertex is adjacent to at most one edge of the subset. As each edge will cover exactly two vertices, this problem is equivalent to the task of finding a matching that covers as many vertices as possible.
Blossom algorithmIn graph theory, the blossom algorithm is an algorithm for constructing maximum matchings on graphs. The algorithm was developed by Jack Edmonds in 1961, and published in 1965. Given a general graph G = (V, E), the algorithm finds a matching M such that each vertex in V is incident with at most one edge in M and is maximized. The matching is constructed by iteratively improving an initial empty matching along augmenting paths in the graph.
