There's a misconception that because cryptocurrency transactions are cryptographically secure, they're also anonymous/private. (Cryptography is used for anonymity in other instances, so that must follow here too, right?) While that may be true for some privacy coins, often with some effort to enable what is an "optional" feature, it isn't true for all cryptos. In many cases, if someone knows both your wallet address(es) and your real identity (id est, an exchange that does KYC), it is possible to trace your crypto activity online, through a blockchain's public ledger. Now, if you're someone like me and value your privacy, you don't necessarily want that information out there. It could fall into the wrong hands, like that of the government or state actors. (They have become good at doing this, according to Investopedia.)

In light of the recent Tornado Cash incident and the developer being arrested (possibly with more to come), it might not be a bad thing to exchange some of one's crypto holdings for privacy coins, such as Monero (XMR) and ZCash (ZEC) and use an exchange such as KuCoin (which doesn't require KYC). I'm certainly considering making that move, just in case the storm doesn't blow over and legal appeals/opposition filings to the heavy-handed over-reactions don't succeed. On that note, let's examine some privacy coins:

• Bytecoin (BCN): Bytecoin has been around since 2012. It is based on the CryptoNote protocol. It uses one-time public keys for each transaction, even if there are multiple transactions per recipient. It also mixes different transactions of similar amounts/values into one. Bytecoin is not widely used, since Monero (XMR) is preferred.
• DeepOnion (ONION): Deep Onion is native to Tor's Onion Router Network. It uses DeepSend to make transactions untraceable, through the use of multi-signature payments for mixing.
• Grin (GRIN): Grin is fairly new, only coming into existence in 2019. It implements the MimbleWimble (MW) protocol.* (No addresses are used. Sender and recipient communicate to create an address on the fly. Only the users involved have access to the data, even if asynchronously.) Viewing blocks doesn't provide any insight into transactions. Grin is not widely used.
• Horizen (ZEN): Like ZEC (see below), Horizen offers shielded Z-addresses and transparent T-addresses. (Sending from a Z-address to a T-address will show the amount received.)
• Monero (XMR): By far the most popular privacy coin listed, Monero is a fork of Bytecoin. (It has subsequently been upgraded to use the RandomX protocol.) It has privacy built in and enabled by default (unlike some of the other ones on this list). The blockchain was created to be opaque. It makes use of one-time-use (stealth) addresses that ensure payments to the same person can't be discerned. Ring transactions hide the amount, routes and origins of transactions.
• ZCash (ZEC): The second most popular privacy coin on this list, ZEC started out as a fork of Bitcoin. One of the key developers is/was Edward Snowden (NSA whistle-blower), who contributed his knowledge of cryptography. Unfortunately, privacy with ZCash is opt-in, but it's easy enough to set up and use if you know how.
• DigiCash (DASH): DASH is a fork of Bitcoin, initially named XCoin. It was widely used by/on the dark Web. The slogan for DASH is "digital cash you can spend anywhere". Dash uses the X11 consensus protocol for PoS. Privacy is ensured through the use of PrivateSend, which is a decentralised coin mixer.
• Private Instant Verified Transactions (PIVX): PIVX is an open-source and PoS cryptocurrency that was forked from DigiCash (DASH) and uses the Zerocoin protocol. PIVX is completely anonymous, fast and has low transaction fees.
• Verge (XVG): Originally named DogecoinDark, Verge is an open-source crypto that uses the TOR network for hiding users' IP addresses. Transactions are intended to be both cheap and fast (less than five seconds). Verge uses POW, which means it is mineable (offering five different algorithms from which to choose).

Warning: Just because a cryptocurrency is designated as a "privacy coin" doesn't guarantee that it is completely anonymous. (At best, a degree of anonymity is achieved through obscurity.) There are complex algorithms and technologies involved. The intricacies and details of implementations need to be carefully considered when choosing one (or more). As always, DYOR!

Conclusion

Obviously, what you choose is up to you, depending on your needs. For me, I'll stick with Monero (XMR) and shielded ZCash (ZEC), since they are popular and have a good track record. However, Grin (GRIN) looks promising and worth investigation.

* MimbleWimble is a stupid name, but a great idea, IMO.

Thumbnail: Photo by Faisal Rahman on Pexels