https://learn.adafruit.com/monochrome-oled-breakouts

This is a library for our Monochrome OLEDs based on SSD1306 drivers

Pick one up today in the adafruit shop! ------> http:https://www.adafruit.com/category/63_98

These displays use SPI to communicate, 4 or 5 pins are required to
interface

Adafruit invests time and resources providing this open source code, please support Adafruit and open-source hardware by purchasing products from Adafruit!

Written by Limor Fried/Ladyada for Adafruit Industries.
Scrolling code contributed by Michael Gregg BSD license, check license.txt for more information All text above must be included in any redistribution

To download. click the DOWNLOADS button in the top right corner, rename the uncompressed folder Adafruit_SSD1306. Check that the Adafruit_SSD1306 folder contains Adafruit_SSD1306.cpp and Adafruit_SSD1306.h

Place the Adafruit_SSD1306 library folder your /libraries/ folder. You may need to create the libraries subfolder if its your first library. Restart the IDE.

You will also have to download the Adafruit GFX Graphics core which does all the circles, text, rectangles, etc. You can get it from https://github.com/adafruit/Adafruit-GFX-Library and download/install that library as well