Official IT Manuals & Documentation

Programming Languages

Python

https://docs.python.org/3/

Java

https://docs.oracle.com/en/java/

JavaScript

https://developer.mozilla.org/en-US/docs/Web/JavaScript

TypeScript

https://www.typescriptlang.org/docs/

https://devdocs.io/c/

C++

https://en.cppreference.com/w/

https://golang.org/doc/

Rust

https://doc.rust-lang.org/book/

Ruby

https://ruby-doc.org/

Swift

https://swift.org/documentation/

Kotlin

https://kotlinlang.org/docs/home.html

https://learn.microsoft.com/en-us/dotnet/csharp/

PHP

https://www.php.net/manual/en/

Perl

https://perldoc.perl.org/

Haskell

https://www.haskell.org/documentation/

Scala

https://docs.scala-lang.org/

Dart

https://dart.dev/guides

Bash

https://www.gnu.org/software/bash/manual/bash.html

Lua

https://www.lua.org/docs.html

Objective-C

https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/ProgrammingWithObjectiveC/Introduction/Introduction.html

Elixir

https://hexdocs.pm/elixir/

Clojure

https://clojure.org/reference/documentation

https://learn.microsoft.com/en-us/dotnet/fsharp/

Groovy

http://groovy-lang.org/documentation.html

MATLAB

https://www.mathworks.com/help/matlab/

Julia

https://docs.julialang.org/en/v1/

PowerShell

https://learn.microsoft.com/en-us/powershell/

VBA

https://docs.microsoft.com/en-us/office/vba/api/overview/

COBOL

https://www.ibm.com/docs/en/cobol-zos

Fortran

https://fortran-lang.org/learn/

Ada

https://www.adacore.com/docs

Assembly

https://www.nasm.us/doc/

Elm

https://guide.elm-lang.org/

Crystal

https://crystal-lang.org/docs/

Nim

https://nim-lang.org/docs.html

ReasonML

https://reasonml.github.io/docs/en/why-reason

Tcl

https://www.tcl-lang.org/documentation.html

https://dlang.org/spec/

Erlang

https://erlang.org/doc/

OCaml

https://ocaml.org/docs/

Smalltalk

http://smalltalk.org/books/

VHDL

https://vhdlwhiz.com/

Verilog

https://www.verilog.com/

Forth

https://www.forth.com/starting-forth/

https://cran.r-project.org/manuals.html

PostScript

https://www.adobe.com/content/dam/acom/en/devnet/postscript/pdfs/PLRM.pdf

ActionScript

https://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/

CoffeeScript

https://coffeescript.org/#documentation

Zig

https://ziglearn.org/

Solidity

https://docs.soliditylang.org/en/v0.8.20/

Pascal

https://www.freepascal.org/docs.html

Awk

https://www.gnu.org/software/gawk/manual/gawk.html

Common Lisp

https://common-lisp.net/documentation/

NATURAL

https://documentation.softwareag.com/nat/nat.htm

Hack

https://docs.hhvm.com/hack/

Delphi

https://docwiki.embarcadero.com/RADStudio/en/Main_Page

https://docs.microsoft.com/en-us/azure/quantum/user-guide/

T-SQL

https://learn.microsoft.com/en-us/sql/t-sql/language-reference?view=sql-server-ver16

ABAP

https://help.sap.com/viewer/index

VB.NET

https://learn.microsoft.com/en-us/dotnet/visual-basic/

Lisp

http://www.lispworks.com/documentation/index.html

AutoHotkey

https://www.autohotkey.com/docs/v2/

https://learn.microsoft.com/en-us/previous-versions/windows/desktop/site/jsharp-sdk-overview

Racket

https://docs.racket-lang.org/

Ring

https://ring-lang.github.io/

SPARK

https://docs.adacore.com/spark2014-docs/

VBScript

https://learn.microsoft.com/en-us/previous-versions//d1wf56tt(v=vs.85)

X++

https://docs.microsoft.com/en-us/dynamics365/fin-ops-core/dev-itpro/dev-ref/xpp-language-reference

Yorick

https://yorick-lang.org/manual/

ZPL

https://zpl-lang.github.io/zpl-documentation/

Algol

https://en.wikipedia.org/wiki/ALGOL

Bourne shell

https://pubs.opengroup.org/onlinepubs/9699919799/utilities/sh.html

Chapel

https://chapel-lang.org/docs/

COQ

https://coq.inria.fr/documentation

Curl

https://curl.se/docs/manual.html

Eiffel

https://www.eiffel.org/doc/technology/eiffel

Elisp

https://www.gnu.org/software/emacs/manual/html_node/elisp/

Factor

https://docs.factorcode.org/content/

GDScript

https://docs.godotengine.org/en/stable/tutorials/scripting/gdscript/

Idris

https://docs.idris-lang.org/en/latest/

https://iolanguage.org/reference/

https://www.jsoftware.com/help/

Jolie

https://jolie-lang.org/doc/

KRL

https://docs.krl.io/

LiveCode

https://livecode.com/resources/

Mirah

https://mirah.org/documentation/

Modula-2

https://modula-2.org/

NetLogo

https://ccl.northwestern.edu/netlogo/docs/

PL/I

https://en.wikipedia.org/wiki/PL/I

RPG

https://www.ibm.com/docs/en/ibm-i/7.2?topic=programming-rpg-language

S-Lang

https://www.jedsoft.org/slang/doc/

SQL

https://www.w3schools.com/sql/

Databases

Oracle Database

https://docs.oracle.com/en/database/

MySQL

https://dev.mysql.com/doc/

Microsoft SQL Server

https://learn.microsoft.com/en-us/sql/

PostgreSQL

https://www.postgresql.org/docs/

MongoDB

https://docs.mongodb.com/

Snowflake

https://docs.snowflake.com/

Redis

https://redis.io/documentation

Elasticsearch

https://www.elastic.co/guide/en/elasticsearch/reference/current/

IBM Db2

https://www.ibm.com/docs/en/db2

SQLite

https://sqlite.org/docs.html

MariaDB

https://mariadb.com/docs

Microsoft Azure SQL Database

https://learn.microsoft.com/en-us/azure/azure-sql/

Amazon DynamoDB

https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Introduction.html

Apache Hive

https://cwiki.apache.org/confluence/display/Hive/Home

Google BigQuery

https://cloud.google.com/bigquery/docs

Neo4j

https://neo4j.com/docs/

FileMaker

https://help.claris.com/en/

Teradata

https://docs.teradata.com/

SAP HANA

https://help.sap.com/viewer/product/SAP_HANA_PLATFORM

Apache Solr

https://solr.apache.org/guide/8_8/

Apache Cassandra

https://cassandra.apache.org/doc/latest/

Greenplum

https://greenplum.org/documentation/

Amazon Redshift

https://docs.aws.amazon.com/redshift/latest/mgmt/welcome.html

Amazon Timestream

https://docs.aws.amazon.com/timestream/latest/developerguide/what-is-timestream.html

ClickHouse

https://clickhouse.com/docs/en/

Couchbase

https://docs.couchbase.com/home/index.html

InfluxDB

https://docs.influxdata.com/influxdb/

PostGIS

https://postgis.net/docs/

TimescaleDB

https://docs.timescale.com/latest/main

Tarantool

https://www.tarantool.io/en/doc/latest/

Dgraph

https://dgraph.io/docs/

RethinkDB

https://rethinkdb.com/docs/

Firebird

https://firebirdsql.org/manual/

Sybase

https://infocenter.sybase.com/help/index.jsp

H2 Database

https://www.h2database.com/html/main.html

CockroachDB

https://www.cockroachlabs.com/docs/

Google Firebase Realtime Database

https://firebase.google.com/docs/database

Cloudant

https://cloud.ibm.com/docs/Cloudant

Exasol

https://docs.exasol.com/

SingleStore

https://docs.singlestore.com/

CrateDB

https://crate.io/docs/

Presto

https://prestodb.io/docs/current/

Apache Ignite

https://ignite.apache.org/docs/latest/

Amazon Neptune

https://docs.aws.amazon.com/neptune/latest/userguide/

Databricks Delta Lake

https://docs.databricks.com/delta/index.html

Google Cloud Firestore

https://firebase.google.com/docs/firestore

CouchDB

https://docs.couchdb.org/en/stable/

Realm

https://www.mongodb.com/realm

Aerospike

https://www.aerospike.com/docs/

Google Cloud Datastore

https://cloud.google.com/datastore/docs

Virtuoso

https://virtuoso.openlinksw.com/dataspace/doc/dav/wiki/Main/

ArangoDB

https://www.arangodb.com/docs/stable/

RavenDB

https://ravendb.net/docs/

Oracle NoSQL

https://docs.oracle.com/en/database/other-databases/nosql-database/

SAP ASE (Sybase)

https://help.sap.com/viewer/product/SAP_ADAPTIVE_SERVER_ENTERPRISE

ScyllaDB

https://docs.scylladb.com/

FoundationDB

https://apple.github.io/foundationdb/

NuoDB

https://www.nuodb.com/resources/official-documentation

OpenTSDB

http://opentsdb.net/docs/build/html/

Apache Kudu

https://kudu.apache.org/docs/

Memcached

https://memcached.org/about

OrientDB

https://orientdb.com/docs/

YugabyteDB

https://docs.yugabyte.com/

FaunaDB

https://docs.fauna.com/fauna/current/

Vertica

https://www.vertica.com/documentation/

Google Bigtable

https://cloud.google.com/bigtable/docs

OpenGauss

https://opengauss.org/zh/docs/

Operating Systems

Linux Kernel

https://www.kernel.org/doc/html/latest/

Ubuntu

https://help.ubuntu.com/

Debian

https://www.debian.org/doc/

Fedora

https://docs.fedoraproject.org/en-US/docs/

CentOS

https://wiki.centos.org/Documentation

OpenWrt

https://openwrt.org/docs/start

FreeBSD

https://www.freebsd.org/doc/

NetBSD

https://netbsd.org/docs/

Linux Systemd

https://www.freedesktop.org/wiki/Software/systemd/

Linux PAM

https://www.linux-pam.org/Linux-PAM-html/Linux-PAM_SAG.html

SELinux

https://selinuxproject.org/page/Main_Page

AppArmor

https://gitlab.com/apparmor/apparmor/wikis/home

Containers & Orchestration

Docker

https://docs.docker.com/

Kubernetes

https://kubernetes.io/docs/home/

OpenShift

https://docs.openshift.com/container-platform/latest/

K3s

https://rancher.com/docs/k3s/latest/en/

Minikube

https://minikube.sigs.k8s.io/docs/

Helm

https://helm.sh/docs/

Argo CD

https://argo-cd.readthedocs.io/en/stable/

Argo Workflows

https://argoproj.github.io/argo-workflows/

Flux

https://fluxcd.io/docs/

Istio

https://istio.io/latest/docs/

Linkerd

https://linkerd.io/2.11/getting-started/

Calico

https://docs.projectcalico.org/

Cilium

https://docs.cilium.io/en/stable/

Rancher

https://rancher.com/docs/

Harbor

https://goharbor.io/docs/

Apache Mesos

http://mesos.apache.org/documentation/latest/

KubeVirt

https://kubevirt.io/user-guide/docs/latest/

Knative

https://knative.dev/docs/

Open Function

https://openfunction.dev/docs

Flannel

https://github.com/flannel-io/flannel/blob/master/Documentation.md

Tekton Pipelines

https://tekton.dev/docs/pipelines/

OpenShift Service Mesh

https://docs.openshift.com/container-platform/latest/service_mesh/service_mesh_index.html

KEDA

https://keda.sh/docs/

Longhorn

https://longhorn.io/docs/

DevOps & CI/CD

Jenkins

https://www.jenkins.io/doc/

GitLab CI

https://docs.gitlab.com/ee/ci/

CircleCI

https://circleci.com/docs/

Travis CI

https://docs.travis-ci.com/

GitHub Actions

https://docs.github.com/en/actions

Azure DevOps

https://learn.microsoft.com/en-us/azure/devops/

Bitbucket

https://support.atlassian.com/bitbucket-cloud/docs/

OpenShift Pipelines

https://docs.openshift.com/container-platform/latest/pipelines/understanding-openshift-pipelines.html

CI/CD Concepts

https://www.redhat.com/en/topics/devops/what-is-ci-cd

Monitoring & Logging

Prometheus

https://prometheus.io/docs/

Grafana

https://grafana.com/docs/

Grafana Loki

https://grafana.com/docs/loki/latest/

Grafana Tempo

https://grafana.com/docs/tempo/latest/

Zabbix

https://www.zabbix.com/documentation/

Nagios

https://assets.nagios.com/downloads/nagioscore/docs/nagioscore/4/en/toc.html

New Relic

https://docs.newrelic.com/

New Relic One

https://docs.newrelic.com/docs/new-relic-one/

Datadog

https://docs.datadoghq.com/

Datadog Agent

https://docs.datadoghq.com/agent/

Sysdig

https://docs.sysdig.com/en/

Netdata

https://learn.netdata.cloud/docs/

Graylog

https://docs.graylog.org/en/4.3/pages/getting_started.html

OpenTelemetry

https://opentelemetry.io/docs/

Prometheus Alertmanager

https://prometheus.io/docs/alerting/alertmanager/

Elasticsearch

https://www.elastic.co/guide/en/elasticsearch/reference/current/

Elastic APM

https://www.elastic.co/guide/en/apm/get-started/current/index.html

Elastic Beats

https://www.elastic.co/guide/en/beats/libbeat/current/index.html

Elastic Stack

https://www.elastic.co/elastic-stack

Splunk

https://docs.splunk.com/Documentation/Splunk/latest/SearchTutorial/WelcometotheSearchTutorial

Sentry

https://docs.sentry.io/

AppDynamics

https://docs.appdynamics.com/

SonarQube

https://docs.sonarqube.org/latest/

SonarCloud

https://sonarcloud.io/documentation

Prometheus Operator

https://github.com/prometheus-operator/prometheus-operator

Configuration Management & Infrastructure as Code

Ansible

https://docs.ansible.com/

Terraform

https://developer.hashicorp.com/terraform/docs

Terraform Registry

https://registry.terraform.io/

SaltStack

https://docs.saltproject.io/en/latest/

Chef

https://docs.chef.io/

Consul

https://www.consul.io/docs

Vault

https://www.vaultproject.io/docs

Nomad

https://www.nomadproject.io/docs

CMake

https://cmake.org/documentation/

OPA (Open Policy Agent)

https://www.openpolicyagent.org/docs/latest/

Open Policy Agent Gatekeeper

https://open-policy-agent.github.io/gatekeeper/website/docs/

Dex

https://dexidp.io/docs/

Kustomize

https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/

Networking & Security

Nginx

https://nginx.org/en/docs/

Apache HTTP Server

https://httpd.apache.org/docs/

Envoy Proxy

https://www.envoyproxy.io/docs

Cloudflare

https://developers.cloudflare.com/docs/

Cilium

https://docs.cilium.io/en/stable/

Calico

https://docs.projectcalico.org/

SELinux

https://selinuxproject.org/page/Main_Page

AppArmor

https://gitlab.com/apparmor/apparmor/wikis/home

JWT (JSON Web Tokens)

https://jwt.io/introduction/

OAuth 2.0

https://oauth.net/2/

OpenID Connect

https://openid.net/connect/

OpenTracing

https://opentracing.io/docs/overview/

Snyk

https://docs.snyk.io/

Sonatype Nexus

https://help.sonatype.com/repomanager3

Falco

https://falco.org/docs/

Tools & Frameworks

Visual Studio Code

https://code.visualstudio.com/docs

JetBrains IntelliJ IDEA

https://www.jetbrains.com/help/idea/

Android SDK

https://developer.android.com/docs

Postman

https://learning.postman.com/docs/

Jupyter

https://jupyter.org/documentation

Gradle

https://docs.gradle.org/current/userguide/userguide.html

Maven

https://maven.apache.org/guides/index.html

Selenium

https://www.selenium.dev/documentation/

Jira

https://confluence.atlassian.com/jira/jira-documentation-938846830.html

Confluence

https://confluence.atlassian.com/doc/confluence-documentation-135922.html

Prettier

https://prettier.io/docs/en/

ESLint (Linting & Formatting)

https://eslint.org/docs/user-guide/getting-started

CakePHP

https://book.cakephp.org/

PowerBuilder

https://docs.appeon.com/powerbuilder/index.html

Cloud Platforms

AWS

https://docs.aws.amazon.com/

Google Cloud Platform

https://cloud.google.com/docs

Microsoft Azure

https://learn.microsoft.com/en-us/azure/

Cloudflare

https://developers.cloudflare.com/docs/

Google Firebase

https://firebase.google.com/docs

Microsoft Intune

https://docs.microsoft.com/en-us/mem/intune/fundamentals/

API & Integration

OpenAPI (Swagger)

https://swagger.io/specification/

GraphQL

https://graphql.org/learn/

REST API

https://restfulapi.net/

gRPC

https://grpc.io/docs/

Kong Gateway

https://docs.konghq.com/gateway/latest/

Tyk API Gateway

https://tyk.io/docs/

Twilio

https://www.twilio.com/docs

Stripe API

https://stripe.com/docs/api

Analytics, Big Data & Messaging

Apache Kafka

https://kafka.apache.org/documentation/

Kafka Connect

https://docs.confluent.io/platform/current/connect/index.html

Kafka Schema Registry

https://docs.confluent.io/platform/current/schema-registry/index.html

KSQLDB

https://ksqldb.io/documentation/

RabbitMQ

https://www.rabbitmq.com/documentation.html

Apache Spark

https://spark.apache.org/docs/latest/

Apache Flink

https://nightlies.apache.org/flink/flink-docs-release-1.14/

Apache Airflow

https://airflow.apache.org/docs/

Apache NiFi

https://nifi.apache.org/docs.html

Apache ZooKeeper

https://zookeeper.apache.org/doc/r3.7.0/

GAMS

https://www.gams.com/latest/docs/

SAS

https://documentation.sas.com/

IoT & Edge

MQTT

http://mqtt.org/documentation

CoAP

https://coap.technology/

Zigbee

https://zigbeealliance.org/solution/zigbee/

LoRaWAN

https://lora-alliance.org/about-lorawan/

Bluetooth

https://www.bluetooth.com/specifications/