Description:
This is a low cost Arduino-compatible ESP32 development board. A 0.96OLED display is on the board. It is very easy for beginners to learn ESP32.

Module:esp-wroom-32 chip

ESP-WROOM-32 is a powerful, generic Wi-Fi+BT+BLE MCU module that targets a wide variety of applications, ranging from low-power sensor networks to the most demanding tasks, such as voice encoding, music streaming and MP3 decoding.

The operating system chosen for ESP32 is freeRTOS with LWIP; TLS 1.2 with hardware acceleration is built in as well. Secure (encrypted) over the air (OTA) upgrade is also supported, so that developers can continually upgrade their products even after
their release.
240 MHz dual core Tensilica LX6 microcontroller with 600 DMIPS Integrated 520 KB SRAM
Integrated 802.11BGN HT40 Wi-Fi transceiver, baseband, stack and LWIP
Integrated dual mode Bluetooth (classic and BLE)
4 MB flash For controlling OLED
Pin 5 is SDA, Pin 4 is SCL
You need to hold "boot" button then click "EN" will go to download mode

Document link: https://github.com/espressif/arduino-esp32
http://www.espressif.com/en/support/download/documents?keys=&field_type_tid%5B%5D=13

Package Included:
1 X ESP8266 ESP-Wroom-32 Wifi Bluetooth Module 1.3’’ OLED
2 X Pin Headers
1 X Base Board