Do I need to buy a Xbox 360 to use my 360 kinect on pc?
The Kinect is just a fancy camera, so no.
You can use it with your PC, assuming that you've set your PC up to work with the Kinect. The following step by step instructions can walk you through the process of getting started with using your Kinect with a computer.
🔍 Identify your Kinect and its Hardware
You've already done part of this step, but effectively there are four different models. Additionally, you'll need to ensure have the required power and connection supplies:
|XBOX 360||The original device launched as an extension to the XBOX 360 console.||You need to buy a dedicated power supply unit / USB cable combination (about $10 USD).|
|Windows||As in Windows 7, the same as XBOX 360 version, only the firmware is more advanced, i.e. allows closer distances to the object.||You will have a power supply unit / USB cable combination as part of your Kinect package.|
|XBOX One||The successor of the earlier Kinect for XBOX 360.||You need to buy a dedicated power supply unit/ USB 3 cable combination (about $10 USD).|
|Windows v2||As in Windows 8+, the same as the XBOX One version, but now for connection to your PC.||You will have a power supply unit / USB cable combination as part of your Kinect package.|
❌ Remove Kinect Software
If you've already attempted to install the Kinect drivers and/or applications, it's wise to uninstall them before proceeding. Since Kinect can technically be used with various operating systems, a simple Google search respective to your OS should suffice in educating you on removal.
Note: Be sure to restart your computer before proceeding after removal. This ensures a fresh start to the installation coming next.
⏳ Install Kinect Software
You need both a Software Development Kit (SDK) for the drivers and a Developers Tool Kit for the examples and tools. Always install the SDK first and the Developers Tool Kit next. You can download the software from Microsoft where you find two versions (v1.7 and v1.8) for both products.
If you have a Kinect for Xbox 360 or a Kinect for Windows you should use v1.7 which runs on Windows 7 (maybe Windows 8 as well). If you have a Kinect for Xbox One or a Kinect for Windows v2 you have to use v1.8 which runs on Windows 8 (maybe Windows 7 as well).
Afterwards you will find the Kinect Studio program and a Developer Toolkit Browser plus some documents in your Windows task menu.
🔌 Connect Your Kinect
First power on your Kinect and then connect it to your computer via a USB port. Wait for at least five minutes. In the meantime you could look at device management on your Windows machine to see what is happening. After a while, you will receive a Device Ready message.
In the device manager you will see that four new devices have been installed:
🧰 Browse Your Kinect Toolkit
Now start the Developer Toolkit Browser for exploring a bunch of ready-to-run demo's and corresponding documentation.
🎥 Explore Kinect Studio
One of the applications is Kinect Studio that supports other programs in working with the Kinect.
💻 Watch It
Furthermore, there are plenty of video tutorials on the topic, here is one of them:
Note: This answer mostly summarizes this instructable.