What is bitcoin?
比特币是什么？
Bitcoin is a kind of digital currency.
比特币是一种数字货币。
You can buy it with dollars or euros, just like you can trade any other currency.
你可以像兑换其他货币一样，用美元、欧元购买比特币。
You store it in an online “wallet.” And with that wallet, you can spend bitcoin online and in the physical world for goods and services.
存入网上“钱包”，然后可以通过这个“钱包”用比特币在网上或现实世界购买物品或服务。
And, of course, bitcoin has a valuation, which you may have heard about because bitcoin's price has fluctuated up and down.
当然，你可能有所耳闻，比特币也有估值，因为比特币的价格会上下波动。
What's different about bitcoin?
比特币有何不同？
Usually, if you pay for something on the Internet, you use a credit or debit card.
如果你在网上买东西，通常你需要信用卡或借记卡。
That card is connected to information about you, such as your name and billing address.
这些卡会绑定你的个人信息，比如你的名字和账单邮寄地址。
You can use bitcoin the same way, but unlike with a credit card, the transactions you make with the currency are completely anonymous.
同样，你可以用比特币在网上消费，但是不同于使用信用卡，使用比特币的交易是完全匿名的交易。
They can't be used to identify you personally.
所以这些交易无法用来识别你的个人身份。
So you can use bitcoin to protect your privacy. Is that why the WannaCry attackers picked it as a form of payment?
你可以用比特币保护自己的个人信息。那么，这是比特币勒索病毒散布者选择用比特币作为支付方式的原因吗？
Possibly. Bitcoin has certainly gained prominence in the news media as a technology that can facilitate crime.
有可能。比特币成为助长犯罪的手段，无疑受到众多新闻媒体的关注。
But even though the identities of people in a bitcoin transaction may be hidden, the public ledger has increasingly helped law enforcement trace the movement of bitcoins from place to place.
但是即使在使用比特币的交易中交易者的身份隐匿，公开的账簿依然能帮助执法人员追踪比特币的去向。
（翻译：红楼里的小石头）