Article in English: Go to https://support.apple.com/en-us/ht204217 in your computer's web browser. This is the website on which Apple lists their different iPod models. At the top of the page, click the iPod option which correlates with your model of iPod. This will take you to the most recent generation of your selected iPod. If you're not sure which iPod model you have, scroll down until you see an iPod which resembles yours. Scroll through the various generations of iPods until you find one which resembles your model. Below the model's generation heading, you'll see a list of features included in the iPod. If the features listed on the site match the features your iPod has, you've found your iPod's generation. If the features listed below the current generation don't match your iPod, scroll down a generation and repeat. If you can't figure out the generation of iPod from the Apple site's visuals—or if you just want to verify your iPod's generation—do the following:  Find your iPod's model number (the five-character code next to "Model" on the back of your iPod). Press Ctrl+F (Windows) or ⌘ Command+F (Mac) to open the "Find" window on the Apple website. Type in your iPod's model number. Find the generation heading above the number.

Summary in Vietnamese:
Mở trang "Identify your iPod model" (Phân biệt model iPod) của Apple. Chọn model. Tìm model của iPod. So sánh model trên trang web với iPod. Tra cứu iPod theo số model.