Through a mathematical algorithm, a private key is like your electronic identification card; the public key is like the lock or gate mechanism that you present your ID card to.

通过一个数学算法，一个私钥如同您的电子身份证；公钥如同您向其出示身份证的锁或门机制。

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The process for registering with M-Pesa is very straightforward: it requires a PIN and an official form of identification (a passport or a national ID card) but there is no need for a bank account or a home address.

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