This is the last time I'm going to do your thinking/research! 
Read this:
Specifically:
Note
There are both 7- and 8-bit versions of I2C addresses.
7 bits identify the device, and the eighth bit determines if it's being written to or read from.
The Wire library uses 7 bit addresses throughout.
If you have a datasheet or sample code that uses 8 bit address, you'll want to drop the low bit (i.e. shift the value one bit to the right), yielding an address between 0 and 127.