user32100: This is about how USB ports/devices work
Lets say i have a USB port on my computer 

If I have an arduino board or something similar, am I able to connect output to Data+ and sort of make my own USB keyboard. 
What I aim to achieve is send without having to receive 

1) Would I need to connect it to both D+ and D- so it forms a circuit in order for the USB port to read the data? (or would the data simply be read and then disappears so I don't have to worry about two wires?)
If Yes: 2) If I manage to forcefully push electricity through the wire onto the Data pins, would I only need one wire?
Else: 3) is this physically impossible and the whole universe would explode if I tried?

user368: USB is a host-managed protocol. A USB device must be able to receive in order to operate, since the host notifies the device when it should send data back to the host.
The D+ and D- lines are not independent; the signaling state of the line is determined by examining both lines regardless of whether the host or the device is transmitting.
USB Made Simple

user4143: D+ and D- are not send and receive. The two signals are complementary to each other and bidirectional.
They form a low voltage differential pair. When one is high the other is low and vice versa.
Both have to be connected for USB signals to get through.
The data is sent down both wires at once, but only in one direction at a time (half duplex). 
There is far more data going through USB than the data you are sending. The data you see is the end result of a complex protocol negotiation between your device and the host.

32100: <p><strong>This is about how USB ports/devices work</strong></p>

<p>Lets say i have a USB port on my computer </p>

<p><a href="https://i.stack.imgur.com/Qzef3.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Qzef3.png" alt="enter image description here"></a></p>

<p>If I have an arduino board or something similar, am I able to connect output to Data+ and sort of make my own USB keyboard. 
<strong>What I aim to achieve is send without having to receive</strong> </p>

<p><a href="https://i.stack.imgur.com/k35HS.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/k35HS.png" alt="enter image description here"></a></p>

<p><strong>1)</strong> Would I need to connect it to both D+ and D- so it forms a circuit in order for the USB port to read the data? (or would the data simply be read and then disappears so I don't have to worry about two wires?)</p>

<p>If Yes: <strong>2)</strong> If I manage to forcefully push electricity through the wire onto the Data pins, would I only need one wire?</p>

<p>Else: <strong>3)</strong> is this physically impossible and the whole universe would explode if I tried?</p>
 368: <p>USB is a host-managed protocol. A USB device <em>must</em> be able to receive in order to operate, since the host notifies the device when it should send data back to the host.</p>

<p>The D+ and D- lines are <em>not</em> independent; the signaling state of the line is determined by examining <em>both</em> lines regardless of whether the host or the device is transmitting.</p>

<p><a href="http://www.usbmadesimple.co.uk/" rel="nofollow noreferrer">USB Made Simple</a></p>
 4143: <p>D+ and D- are not send and receive. The two signals are complementary to each other and bidirectional.</p>

<p>They form a <em>low voltage differential pair</em>. When one is high the other is low and vice versa.</p>

<p>Both have to be connected for USB signals to get through.</p>

<p>The data is sent down both wires at once, but only in one direction at a time (half duplex). </p>

<p>There is far more data going through USB than the data you are sending. The data you see is the end result of a complex protocol negotiation between your device and the host.</p>
