---
title: InfluxDB concepts
description: Learn key concepts in InfluxDB OSS.
url: https://docs.influxdata.com/influxdb/v1/concepts/
estimated_tokens: 607
product: InfluxDB OSS v1
version: v1
---

# InfluxDB concepts

This page documents an earlier version of InfluxDB OSS. [InfluxDB 3 Core](/influxdb3/core/) is the latest stable version.

Understanding the following concepts will help you get the most out of InfluxDB.

## [InfluxDB file system layout](/influxdb/v1/concepts/file-system-layout/)

The InfluxDB file system layout depends on the operating system, package manager, or containerization platform used to install InfluxDB.

## [Compare InfluxDB to SQL databases](/influxdb/v1/concepts/crosswalk/)

Differences between InfluxDB and SQL databases.

## [In-memory indexing and the Time-Structured Merge Tree (TSM)](/influxdb/v1/concepts/storage_engine/)

InfluxDB storage engine, in-memory indexing, and the Time-Structured Merge Tree (TSM) in InfluxDB OSS.

## [InfluxDB design insights and tradeoffs](/influxdb/v1/concepts/insights_tradeoffs/)

Optimizing for time series use case entails some tradeoffs, primarily to increase performance at the cost of functionality.

## [InfluxDB glossary](/influxdb/v1/concepts/glossary/)

Terms related to InfluxDB OSS.

## [InfluxDB key concepts](/influxdb/v1/concepts/key_concepts/)

Covers key concepts to learn about InfluxDB.

## [InfluxDB schema design and data layout](/influxdb/v1/concepts/schema_and_data_layout/)

Improve InfluxDB schema design and data layout to reduce high cardinality and make your data more performant.

## [Time Series Index (TSI) details](/influxdb/v1/concepts/tsi-details/)

Enable and understand the Time Series Index (TSI).

## [Time Series Index (TSI) overview](/influxdb/v1/concepts/time-series-index/)

The Time Series Index (TSI) storage engine supports high cardinality in time series data.