> ## Documentation Index > Fetch the complete documentation index at: https://docs.nx1cloud.com/llms.txt > Use this file to discover all available pages before exploring further. # Glossary > Definitions of key terms used across NexusOne documentation. This glossary defines key terms used in the NexusOne documentation. ### A * **Apache Airflow** An open source platform used internally at NexusOne to author, schedule, and monitor tasks or jobs represented as [DAGs](#d). See also [Engineer](#e), [Ingest](#i), or the [Apache Airflow](https://github.com/apache/airflow) repository. * **Apache APISIX API Gateway** An open source platform used internally at NexusOne to manage traffic from microservices and large language models. See also the [Apache APISIX API Gateway](https://github.com/apache/apisix) repository. * **Apache Gravitino** An open source platform used internally at NexusOne to provide metadata management and governance across data lakes and warehouses. See also the [Apache Gravitino](https://github.com/apache/gravitino) repository. * **Apache Iceberg** An open source table format used internally at NexusOne to provide a unified way to access data in a data lake. See also [Ask](#a), [Discover](#d), [Engineer](#e), [Quality](#q), or the [Apache Iceberg](https://github.com/apache/iceberg). * **Apache Kyuubi** An open source platform that acts as a gateway so that you can run SQL queries against Apache Spark engines. See also the [Apache Kyuubi](https://github.com/apache/kyuubi) repository. * **Apache Ranger** An open source platform used internally at NexusOne that uses policies to manage access control to a data platform. See also the [Apache Ranger](https://github.com/apache/ranger) repository. * **Apicurio Schema Registry** An open source platform used internally at NexusOne to store, share, and manage the structured definitions of data used in events or APIs. * **Apache Spark** An open source platform used internally at NexusOne to provide a data processing layer for large data analytics. See also the [Apicurio Schema Registry](https://github.com/Apicurio/apicurio-registry) repository. * **Apache Superset** An open source platform used internally at NexusOne that interactively analyzes and visualizes data. See also [Discover](#d), [Metabase](#m), or the [Apache Superset](https://github.com/apache/superset) repository. * **Ask** A NexusOne feature that generates SQL commands for interacting with ingested data, so you can gain meaningful insights. See also [Ask Overview](/documentation/ai/overview/ask). ### B * **Bucket** A container that stores data in the Amazon S3 service. See also [Ingest](#i). ### C * **Catalog** A group of similar items or data. It has several meanings: * **DataHub**: Groups related datasets and assets such as Topics, Views, or Dashboards, for easier discovery. * **Iceberg**: Provides a consistent way to create, load, and drop tables across different storage systems. * **Trino**: Defines a connection to a data source containing schemas and tables. * **Certificate manager** A digital credential manager used internally at NexusOne to manage web domain names in a Kubernetes cluster, ensuring that web communication between clients and services is secure. * **Cluster** A group of Kubernetes nodes and pods that run open source tools used by NexusOne. * **CSV - Comma-Separated Values** A file format for storing tabular data by separating each value with a comma. You can ingest CSV files into NexusOne. See also [Ingest](#i). ### D * **DAG - Directed Acyclic Graph** A Directed Acyclic Graph contains several tasks that execute from left to right. At NexusOne, DAGs execute when you ingest data or schedule SQL commands to run at specific times. See also [Apache Airflow](#a), [Engineer](#e), or [Ingest](#i). * **Dashboard** A visual user interface displaying ingested or processed data as graphs, charts, or other visual elements. See also [Discover](#d). * **Data API and API key** A way to manage data API endpoints and ensure secure access to the data via the data API endpoints. * **Database** A collection of data stored in tabular format and made available as a software package. You reference a database as a data source when it's ingested into NexusOne or when it's used as a Trino catalog by the Govern feature. * **Data format** A specific way to encode data. This could be in `csv`, `parquet`, or other formats. * **DataHub** An open source platform used internally at NexusOne to provide metadata for your ingested data. This metadata displays the lineage of your data, such as which storage location stores the data, and what Spark operation processed it. See also [Govern](#g), or the [DataHub](https://github.com/datahub-project/datahub) repository. * **Data ingestion** See also [Ingest](#i). * **Data insight** See also [Insight](#i). * **Data lake** A centralized data store for all types of data, such as structured, semi-structured, and unstructured. This allows users and apps to access and analyze the data from a single location. * **Data mirroring** The process of ingesting a database into NexusOne and then creating a copy of it. See also [Ingest](#i). * **Data pipeline** An automated way to ingest and transform data. * **Data product** A DataHub feature used to organize and manage tables, views, and other data assets. * **Data source** A platform that stores data and provides it when requested. This could be different vendor databases, such as MongoDB and PostgreSQL, or a data warehouse like Snowflake. On NexusOne, Trino provides access to these data sources. * **Data warehouse** A large, centralized data store that contains structured and semi-structured data. It's often used for analytics and reporting because it includes both current and historical data. * **Debezium** An open source server used internally at NexusOne to capture table changes from an ingested Database and mirroring it into another database. See also the [Debezium](https://github.com/debezium/debezium) repository. * **Discover** A NexusOne feature that launches the Superset platform. See also [Discover Overview](/documentation/catalog-and-models/overview/discover). * **Domain** A logical way to categorize related data using DataHub. See also [Ask](#a), [Engineer](#e), or [Ingest](#i). ### E * **Engineer** A NexusOne feature that transforms your data. It allows you to select one or more catalogs. See also [Engineer](/documentation/data-pipeline/overview/engineer). * **ETL - Extract, Transform, and Load** A process that's used to integrate data from multiple sources, [transform](/documentation/data-pipeline/overview/engineer#common-operations) it, and then write the result to a target data store. See also [Ingest](#i). * **External DNS Manager** An open source tool for making Kubernetes resources managed by NexusOne discoverable to public domain name servers. See also the [External DNS Manager](https://github.com/kubernetes-sigs/external-dns) repository. ### F * **File format** See also [Data format](#d). ### G * **Govern** A NexusOne feature that manages user or group access to NexusOne features and data sources. See also [Govern Overview](/documentation/govern/overview). * **Group** A collection of users who belong to the same department or share similar responsibilities. ### H * **Health check** A way to verify if the API is operational. * **Hosted apps** A NexusOne feature that lets you launch several open source platform apps hosted on NexusOne. See also, [JupyterHub](#g) or [Trino](#t). ### I * **IAM - Identity and Access Management** A sub-feature of the NexusOne Govern feature. It's used to manage roles assigned to users, groups, and tags. See also [Govern](#g). * **IAM group** See also [Group](#g). * **IAM role** See also [Role](#r). * **Ingest** The process of adding data to a system. It's also a NexusOne feature used to add a file, database, or lakehouse. See also [Ingest Overview](/documentation/data-pipeline/overview/ingest). * **Insight** The result of getting meaningful information by examining data. It's also a NexusOne feature that analyzes data and presents insights. See also [Ask](#a). ### J * **Job** An Apache Spark operation scheduled in Apache Airflow. This is often found when using the Engineer, Ingest, or Monitor features on NexusOne. See also [Monitor](#m). * **JupyterHub** An open source platform that you can launch from the Hosted Apps feature. It's helpful when you are developing and testing [DAGs](#d) that orchestrate [ETL](#e) pipelines. See also the [JupyterHub](https://github.com/jupyterhub/jupyterhub) repository. ### K * **Keda** An open source platform used for auto-scaling Kubernetes workloads managed internally at NexusOne. See also the [Keda](https://github.com/kedacore/keda) repository. * **Keycloak** An open source platform that provides authentication to apps and users. At NexusOne, it's used to manage user access and authentication. See also the [Keycloak](https://github.com/keycloak/keycloak) repository. * **Kubernetes** An open source tool used to orchestrate apps deployed at NexusOne. All apps are internally managed by the NexusOne team. See also the [Kubernetes](https://github.com/kubernetes/kubernetes) repository. ### L * **Lakehouse** A data architecture that combines a data lake and a data warehouse. See also [Ingest](#i). * **LLM - Large Language Model** An artificial intelligence chatbot trained with a huge amount of data. In NexusOne, LLMs generate SQL queries you can use to gather data insights, check data quality, or transform data. See also [Ask](#a), [Engineer](#e), or [Quality](#q). ### M * **Metabase** A more user-friendly open source platform used internally at NexusOne to interactively analyze and visualize ingested data. See also [Apache Superset](#a), [Ask](#a), [Discover](#d), or the [Metabase](https://github.com/metabase/metabase) repository. * **Metadata** Data that describes the content of another data. See also [Apache Gravitor](#a) and [DataHub](#d). * **Monitor** A NexusOne feature for viewing all scheduled, running, failed, or completed jobs. ### N * **NexusOne** The brand name of the Nexus Cognitive software platform. ### O * **Ollama** An open source platform used internally at NexusOne to provide access to a local LLM from companies such as OpenAI and Google. See also [Ask](#i), [Engineer](#e), [Quality](#q), or the [Ollama](https://github.com/ollama/ollama) repository. * **OpenFaaS - Open Function as a Service** An open source platform that allows the NexusOne team to deploy serverless functions on Kubernetes. See also the [OpenFaaS](https://github.com/openfaas/faas) repository. * **Open source** Software whose source code is publicly available on the internet and distributed under a license. NexusOne uses several open source platforms, and the team actively contributes to them as well. * **ORC - Optimized Row Columnar** A file format that stores data as columns. Unlike Parque files, ORC files are more efficient for write-heavy workloads. You can ingest ORC files into NexusOne. See also [Ingest](#i). ### P * **Parquet** A file format type that you can ingest into NexusOne. Unlike row-based file formats such as CSV, Parquet stores data as columns. This makes querying the data faster. See also [Ingest](#i). * **Permission** See also Permission boundary. * **Permission boundary** For restricting access to features for specific ingested data associated with a tag. You do this by assigning specific roles to the tag. See also [Govern](#g). * **PyTorch** An open source Python library used internally at NexusOne to build and train deep learning models. See also the [PyTorch](https://github.com/pytorch/pytorch) repository. ### Q * **Quality** A NexusOne feature that allows you to check if your ingested data meets a defined goal. See also [Quality](/documentation/data-pipeline/overview/quality). * **Query** The process of talking to ingested data in NexusOne using the Trino SQL syntax. See also [Apache Superset](#a) or [Metabase](#m). ### R * **Ray** An open source Python library used internally at NexusOne to scale machine learning workloads. See also the [Ray](https://github.com/ray-project/ray) repository. * **Redis** An open source server used internally at NexusOne for caching data apps. See also the [Redis](https://github.com/redis/redis) repository. * **Reporting cycle** The process of consistently running a SQL command using the NexusOne Ask feature, so you can gather data insights. See also [Ask](#a). * **Role** A set of permissions grouped under a name. Within NexusOne, the default roles represent specific features such as ingesting or transforming data. Custom roles also exists, these are a combination of several default roles. See also [Govern](#g). * **Rule** A SQL command scheduled to execute at specific times of the day using Apache Airflow. See also [Engineer](#e) and [Quality](#q). ### S * **S3** An Amazon cloud storage service used for storing large amounts of object data. NexusOne stores ingested data in S3. * **Schedule** The process of telling a task or job to run at specific times of the day. See also [Engineer](#e), [Ingest](#i). * **Schema** The structure of a database. When ingesting data into NexusOne, you must specify a schema. See also [Apache Superset](#a) or [Metabase](#m). * **SQL - Structured Query Language** A programming language used to interact with ingested data. NexusOne only supports the Trino SQL syntax. See also [Ask](#a), [Engineer](#e), or [Quality](#q). * **SSO - Single sign on** The process of logging into several apps within NexusOne using your single NexusOne credentials. ### T * **Table** A collection of data represented in rows and columns. When ingesting data into NexusOne, you must specify a table. See also [Apache Superset](#a) or [Metabase](#m). * **Tag** An optional name given to ingested data within NexusOne. NexusOne can assign a role to a tag to ensure that the tagged data can only use specific NexusOne features. See also [Ingest](#i) or [Govern](#g). * **Task** See [Job](#j). * **Trino** An open source SQL query engine used within NexusOne. See also [Apache Superset](#a) or [Metabase](#m). ### U * **User** A logical identity assigned to employees interacting with NexusOne. See also [Govern](#g). ### V * **Visualize** The process of seeing insights from ingested data on a user interface. See also [Apache Superset](#a) or [Metabase](#m). ### W * **Warehouse** See also [Data warehouse](#w). ### X * **XLSX - Excel Open XML Spreadsheet** A file format used to represent data. You can ingest XLSX files into NexusOne. See also [Ingest](#i). * **XML - eXtensible Markup Language** A file format used to represent data using elements. For example, NexusOne . You can ingest XML files into NexusOne. See also [Ingest](#i).