This document will help users quickly use FlashDB on the demo platform and experience the actual use of FlashDB
## basic concepts
- **Key-Value Database (KVDB)**: It is a non-relational database that stores data as a collection of key-value pairs, where the key is used as a unique identifier. KVDB has simple operation and strong scalability.
- **Time Series Data (TSDB)**: Time Series Database (TSDB), which stores data in **time sequence**. TSDB data has a timestamp, a large amount of data storage, and high insertion and query performance.
- **Time series log (TSL)**: TSL (Time series log) is the abbreviation of each record in TSDB.
- **Blob**: In a computer, blob is often a field type used to store binary files in a database. In FlashDB, both KV and TSL use the blob type for storage, which can be compatible with any variable type.
- **Iterator**: It allows users to visit every element in the container through a specific interface without knowing the underlying implementation. Both TSDB and KVDB support traversal access to the database through iterators.
## Functional block diagram
Through the following functional block diagram, you can roughly understand the FlashDB functional module division
In the `demos` directory of the project, the following demonstration platforms are currently provided. You can choose a platform and experience the running process of FlashDB on a real machine.