You can't use cash for online purchases, but the new digital current Bitcoin is the next best thing. Unlike other currencies, which are either commodity backed, like the gold standard, or politically backed, like the Federal Reserve, Bitcoins are mathematically backed by complex computer algorithms.
Additionally, Bitcoin transactions are virtually untraceable, much like cash exchanges, allowing users to purchase goods or services online without leaving a trace. Also, with an increasing number of companies that accept bitcoins, completely switching to this anonymous online currency is becoming more viable every day.
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