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Formats & Serialization

How data is encoded on the wire and at rest. 48 in the catalog.

StandardWhat it is
ActivityStreams Activity Streams 2.0 is a W3C Recommendation defining a JSON-based syntax and vocabulary for representing social activities and objects. It is the ...
Agent Skills Open standard for extending AI agents with specialized knowledge and workflows. A skill is a folder containing a SKILL.md file with YAML frontmatte...
Apache Arrow Apache Arrow is a language-independent columnar memory format specification for flat and hierarchical data, optimized for analytics on modern hardw...
Apache Hudi Apache Hudi is an open table format built around incremental processing — upserts, deletes and change streams over data lake tables. Where the othe...
Apache Iceberg Apache Iceberg is an open table format for very large analytic datasets sitting on object storage. It adds a metadata layer above the data files — ...
Apache ORC Apache ORC (Optimized Row Columnar) is a self-describing, type-aware columnar file format for large-scale data processing. It provides efficient co...
Apache Thrift Apache Thrift is an interface definition language and binary RPC framework for building cross-language services. It generates client and server stu...
Avro Apache Avro is a data serialization system that provides compact binary encoding of structured data along with schema definitions, enabling efficie...
Binary Format A binary format encodes data as compact bytes rather than human-readable text, trading readability for smaller payloads and faster parsing. In APIs...
CBOR CBOR (Concise Binary Object Representation, RFC 8949) is a compact binary data format based on the JSON data model. It is designed for small code s...
CSS CSS (Cascading Style Sheets) is the W3C standard language for describing the presentation of documents written in HTML and other markup - controlli...
CSV CSV (Comma-Separated Values) is a simple tabular text format standardized in RFC 4180 for the text/csv media type. It is ubiquitous for data import...
Configuration Language A configuration language is a formal, usually declarative notation for describing how software and infrastructure should be set up — covering forma...
DFDL DFDL (Data Format Description Language) is a modeling language, standardized by the Open Grid Forum, for describing general text and binary data fo...
Data Format A data format is the convention used to encode, structure, and serialize information so it can be stored, transmitted, and reliably parsed between ...
Delta Lake Delta Lake is an open table format and transaction protocol that brings ACID transactions, versioning and schema enforcement to data lakes. Origina...
File Format A file format is a standardized way of encoding and structuring data so that it can be written, stored, exchanged, and reliably read back by differ...
Fixed Format Fixed format (or fixed-width) is a data layout where each field occupies a predetermined number of character positions rather than being separated ...
GeoJSON GeoJSON (RFC 7946) is a JSON-based format for encoding geographic data structures such as points, lines, and polygons with their attributes. It is ...
HTML HTML (HyperText Markup Language) is the standard markup language for structuring documents and content on the web, defining elements like headings,...
HTML5 HTML5 is the fifth major revision of the HyperText Markup Language, adding semantic elements, native audio and video, canvas graphics, and browser ...
Internet Assigned Numbers Authority (IANA) IANA media types, also known as MIME types, are names for the types of data that are transmitted over the internet. They identify the format and na...
JCR JCR (Content Repository API for Java) is a Java specification, defined by JSR 170 and JSR 283, for accessing content repositories in a uniform way,...
JMESPath JMESPath is a formally specified query language for JSON that lets you declaratively extract and transform elements from a document. It is widely e...
JSON JSON (JavaScript Object Notation) is a lightweight, text-based data format used for storing and exchanging data. It is easy for humans to read and ...
JSON Binding JSON Binding (JSON-B / Jakarta JSON Binding) is a standard Java API for converting Java objects to and from JSON documents, giving developers a dec...
JSON Processing JSON Processing (JSON-P / Jakarta JSON Processing) is a standard Java API for parsing, generating, querying, and transforming JSON, offering both a...
JSON Web Token JWT (JSON Web Token) is a compact, self-contained, and secure method for transmitting information between parties as a JSON object. JWT has become ...
JSONPath JSONPath is a query language used to extract, filter, and manipulate data from JSON (JavaScript Object Notation) structures. It provides a syntax s...
KML KML (Keyhole Markup Language) is an OGC standard XML grammar for expressing geographic annotation and visualization. It is used to display features...
MARC MARC is the bibliographic data format libraries have shared catalogue records in since the 1960s, maintained by the Library of Congress. Its succes...
MXML MXML is an XML-based markup language, introduced by Macromedia and later maintained by Adobe, for declaratively laying out the user interfaces and ...
Markdown Markdown is a lightweight markup language that uses plain text formatting syntax (such as asterisks for emphasis, hashes for headings, and brackets...
Markup Language A markup language is a system for annotating a document with tags or symbols that are syntactically distinguishable from the text, encoding structu...
MessagePack MessagePack is an efficient binary serialization format that lets you exchange data among multiple languages like a more compact JSON. It is optimi...
ORCID ORCID provides a persistent identifier for a researcher, plus an API for reading and writing the record of their affiliations, works and funding. I...
PDF PDF (Portable Document Format), standardized as ISO 32000, is a fixed-layout document format that preserves the exact appearance of text, fonts, gr...
Parquet Apache Parquet is an open source, column-oriented data file format designed for efficient data storage and retrieval. It provides efficient data co...
Protocol Buffers Protocol Buffers (protobuf) is Google's language- and platform-neutral mechanism for serializing structured data, defined by a .proto schema and en...
Regular Expressions A sequence of characters that define a search pattern, commonly used for string matching, validation, and text manipulation in programming and data...
Semantic Versioning (SemVer) Semantic versioning (SemVer) is a versioning system designed to convey meaningful information about software updates through a standardized format....
TOML TOML (Tom's Obvious Minimal Language) is a configuration file format designed to be easy to read and to map unambiguously to a hash table. It has a...
Table Format An open table format defines how large analytic datasets are organized as tables on top of files in object storage, adding a metadata layer that tr...
UTF-8 UTF-8 is the recommended character encoding for APIs because it ensures compatibility, efficiency, and universality. Here’s why you should use UTF-...
XML XML (Extensible Markup Language) is a markup language and data format that defines rules for encoding documents in a way that is both human-readabl...
XSLT XSLT (Extensible Stylesheet Language Transformations) is a language for transforming XML documents into other formats such as HTML, plain text, or ...
YAML YAML (YAML Ain't Markup Language) is a human-readable, data serialization format commonly used for configuration files and data exchange between pr...
cXML cXML is an XML-based protocol for business-to-business procurement transactions — purchase orders, order confirmations, invoices, and the PunchOut ...
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