A keyboard generates two scan codes when the user types a key-one when the user presses the key and another when the user releases the key.

当用户按键时候会产生两个扫描码——一个是按下的时候产生的，另外一个是当用户手释放的时候产生的。

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Smartphones also typically feature cameras with a macro mode that allows automatic focus over very short distances to scan codes that appear in a newspaper or magazine.

智能手机还带有具有微距模式的摄像头，这些摄像头可以短距离自动对焦扫描出现在报纸和杂志上的条码。

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While you can use it to scan typical barcodes and look up pricing on items, the greatest feature is using it for scanning QR Codes.

你可以用它扫描一般的二维码来查看物品价格，但是它最好玩的是可以用来扫描QR码（详情戳我）。

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An innovative ISBN scanner allows to scan ISBN codes so you can create your own wish-list and search on supported online libraries and book stores.

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Buyers already have cameras that can scan bar codes and provide both the quantity and quality of information that result in rational pricing and informed decision-making.

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According to comScore, another research company, more than two-thirds of Americans and Europeans who scan QR codes do so in order to obtain information about a product.

ECONOMIST: After many false starts, QR codes are finally taking off