diff --git a/.vscode/settings.json b/.vscode/settings.json
index 8d7bd73..ead3cbc 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -145,6 +145,7 @@
         "fileglob",
         "firewalld",
         "flatpak",
+        "fluentd",
         "freshclam",
         "gbps",
         "gcloud",
diff --git a/knowledge base/beats.md b/knowledge base/beats.md
new file mode 100644
index 0000000..9007ff0
--- /dev/null
+++ b/knowledge base/beats.md	
@@ -0,0 +1,69 @@
+# Beats
+
+TODO
+
+Lightweight, free and open platform for single-purpose data shippers.
+
+Part of the Elastic Stack along with [ElasticSearch], [Kibana] and [Logstash].
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Installation and configuration</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Main repository]
+- [ElasticSearch], [Kibana] and [Logstash]: the rest of the Elastic stack
+
+### Sources
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+[elasticsearch]: elasticsearch.md
+[kibana]: kibana.md
+[logstash]: logstash.md
+
+<!-- Files -->
+<!-- Upstream -->
+[main repository]: https://github.com/elastic/beats
+[website]: https://www.elastic.co/beats
+
+<!-- Others -->
diff --git a/knowledge base/elasticsearch.md b/knowledge base/elasticsearch.md
new file mode 100644
index 0000000..e9dd44f
--- /dev/null
+++ b/knowledge base/elasticsearch.md	
@@ -0,0 +1,77 @@
+# ElasticSearch
+
+TODO
+
+Search and analytics suite.<br/>
+Makes it easy to ingest, search, visualize, and analyze data.
+
+Part of the Elastic Stack along with Beats, [Kibana] and [Logstash].
+
+Use cases: application search, log analytics, data observability, data ingestion, others.
+
+Forked by Amazon into OpenSearch after Elastic's [2021 license change announcement].
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Installation and configuration</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Main repository]
+- [OpenSearch], open source fork by Amazon
+- [Beats], [Kibana] and [Logstash]: the rest of the Elastic stack
+
+### Sources
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+[beats]: beats.md
+[kibana]: kibana.md
+[logstash]: logstash.md
+[opensearch]: opensearch.md
+
+<!-- Files -->
+<!-- Upstream -->
+[2021 license change announcement]: https://www.elastic.co/blog/elastic-license-update
+[main repository]: https://github.com/elastic/elasticsearch
+[website]: https://www.elastic.co/elasticsearch
+
+<!-- Others -->
diff --git a/knowledge base/fluent bit.md b/knowledge base/fluent bit.md
new file mode 100644
index 0000000..708cebb
--- /dev/null
+++ b/knowledge base/fluent bit.md	
@@ -0,0 +1,65 @@
+# Fluent Bit
+
+TODO
+
+Lightweight and highly scalable logging and metrics processor and forwarder.
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Installation and configuration</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Main repository]
+- [Fluentd]
+
+### Sources
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+[fluentd]: fluentd.md
+
+<!-- Files -->
+<!-- Upstream -->
+[main repository]: https://github.com/fluent/fluent-bit
+[website]: https://www.fluentbit.io/
+
+<!-- Others -->
diff --git a/knowledge base/fluentd.md b/knowledge base/fluentd.md
new file mode 100644
index 0000000..dea1aa1
--- /dev/null
+++ b/knowledge base/fluentd.md	
@@ -0,0 +1,64 @@
+# Fluentd
+
+TODO
+
+Open-Source log collector.
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Installation and configuration</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Main repository]
+- [Fluent Bit]
+
+### Sources
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+[fluent bit]: fluent%20bit.md
+<!-- Files -->
+<!-- Upstream -->
+[main repository]: https://github.com/fluent/fluentd
+[website]: https://www.fluentd.org/
+
+<!-- Others -->
diff --git a/knowledge base/kibana.md b/knowledge base/kibana.md
new file mode 100644
index 0000000..fb2d39d
--- /dev/null
+++ b/knowledge base/kibana.md	
@@ -0,0 +1,69 @@
+# Kibana
+
+TODO
+
+Browser-based analytics and search dashboard for [ElasticSearch].
+
+Part of the Elastic Stack along with Beats, [ElasticSearch] and [Logstash].
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Installation and configuration</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Main repository]
+- [Beats], [ElasticSearch] and [Logstash]: the rest of the Elastic stack
+
+### Sources
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+[beats]: beats.md
+[elasticsearch]: elasticsearch.md
+[logstash]: logstash.md
+
+<!-- Files -->
+<!-- Upstream -->
+[main repository]: https://github.com/elastic/kibana
+[website]: https://www.elastic.co/kibana
+
+<!-- Others -->
diff --git a/knowledge base/logstash.md b/knowledge base/logstash.md
new file mode 100644
index 0000000..23f3ed9
--- /dev/null
+++ b/knowledge base/logstash.md	
@@ -0,0 +1,69 @@
+# Title
+
+TODO
+
+Server-side data processing pipeline that ingests data, transforms it, and then sends the results to any collector.
+
+Part of the Elastic Stack along with Beats, [ElasticSearch] and [Kibana].
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Installation and configuration</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Main repository]
+- [Beats], [ElasticSearch] and [Kibana]: the rest of the Elastic stack
+
+### Sources
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+[beats]: beats.md
+[elasticsearch]: elasticsearch.md
+[kibana]: kibana.md
+
+<!-- Files -->
+<!-- Upstream -->
+[main repository]: https://github.com/elastic/logstash
+[website]: https://website/
+
+<!-- Others -->
diff --git a/knowledge base/opensearch.md b/knowledge base/opensearch.md
index c72da49..e827bd0 100644
--- a/knowledge base/opensearch.md	
+++ b/knowledge base/opensearch.md	
@@ -1,6 +1,6 @@
-# Title
+# OpenSearch
 
-Search and analytics suite forked from ElasticSearch by Amazon.<br/>
+Search and analytics suite [forked from ElasticSearch by Amazon][stepping up for a truly open source elasticsearch].<br/>
 Makes it easy to ingest, search, visualize, and analyze data.
 
 Use cases: application search, log analytics, data observability, data ingestion, others.
@@ -268,6 +268,8 @@ Refer
 - [Index management]
 - [Index settings]
 - [Elasticsearch Index Lifecycle Management & Policy]
+- [Top 14 ELK alternatives in 2024]
+- [Stepping up for a truly open source Elasticsearch]
 
 <!--
   Reference
@@ -302,3 +304,5 @@ Refer
 [lucene]: https://lucene.apache.org/
 [okapi bm25]: https://en.wikipedia.org/wiki/Okapi_BM25
 [setting up hot-warm architecture for ism in opensearch]: https://opster.com/guides/opensearch/opensearch-data-architecture/setting-up-hot-warm-architecture-for-ism/
+[stepping up for a truly open source elasticsearch]: https://aws.amazon.com/blogs/opensource/stepping-up-for-a-truly-open-source-elasticsearch/
+[top 14 elk alternatives in 2024]: https://signoz.io/blog/elk-alternatives/
diff --git a/knowledge base/opentelemetry.md b/knowledge base/opentelemetry.md
new file mode 100644
index 0000000..7c277f2
--- /dev/null
+++ b/knowledge base/opentelemetry.md	
@@ -0,0 +1,64 @@
+# OpenTelemetry
+
+TODO
+
+High-quality, ubiquitous, and portable telemetry to enable effective observability.
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<!-- Uncomment if used
+<details>
+  <summary>Installation and configuration</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Main project]
+- [Documentation]
+
+### Sources
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+<!-- Files -->
+<!-- Upstream -->
+[documentation]: https://opentelemetry.io/docs/
+[main project]: https://github.com/open-telemetry
+[website]: https://opentelemetry.io/
+
+<!-- Others -->