So data, one thing to note is that data is put into a buffer before sending. And so there are functions for each one of these things. You start transmission, you send data, end transmission. You start the communication, you send a bunch of data. So here's a really rough, high level overview of what your communication will look like from the master point of view. So if you give no address, then you're a Master. So if you don't pass an address, see masses don't need addresses, right? Masses they need addresses to talk to Slaves, but if you're not a Slave, you don't need an address. And it's address is whatever the address argument was. But if you call Wire.begin with an address as an argument, some number between 0 and 127, then that makes the Arduino a Slave. Now, if you call Wire.begin with no arguments, that makes the Arduino the Master. And so that hardware is initialized by calling Wire.begin. So, in the micro controller, the ATmega328, it has hardware dedicated to I2C and dedicated to placing and doing all this stuff and putting start conditions, stop conditions and all that. Then to initialize the library, start off all the I2C operations, you gotta call wire.begin, and you would do this in your setup. Include, in this case it's Wire.h, so that's the header file. So first, to start off using library, like with all libraries you get start off with a hashtag, include with appropriate hashtag. But the Wire Library is what accesses I2C. Maybe it's the license lease name or stuff, I don't really don't. Why they don't call it I2C, I'm not sure. So the Wire Library is used to access I2C. They are doing a library that supports I2C, so that's called Wire.

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