The cryptocurrency market, which consists of bitcoin and several other major digital currencies, crumbled June 22 as the majority of the coins dipped by up to 10 percent due to six exchanges in Japan that were ordered by the Financial Services Agency, its financial watchdog, to improve their current practices, and as two exchanges were hacked within an 11-day period.
It is important investors realize not all exchanges and brokers that offer delivery of the underlying Bitcoin are created equal. Some firms have fallen victim to theft by hackers who have stolen Bitcoin belonging to clients whose money was held at the exchanges. Meanwhile, other Bitcoin exchanges have gone bankrupt (as in the case of Mt. Gox),  as a result of fraud or mismanagement.
Learn to value coins in BTC. Ether aside, Bitcoin is the current primary currency of the crypto economy (i.e., its what you have to use to buy most altcoins). Those new to crypto tend to value things in dollars. Meanwhile, even seasoned cash traders value coins in dollars. However, enough crypto traders will value coins in BTC for it to matter. If you aren’t aware of the BTC charts, you won’t be able to properly understand the trends everyone else is analyzing and reacting to. You don’t have to make getting more BTC your goal, but you must have the BTC prices of altcoins on your radar. There are times when all coins move up, but altcoins steadily lose value against Bitcoin. Those who know will be the first to dump altcoins for Bitcoin; this will set off a vicious cycle that can result in the stagnation of altcoin prices.
The crypto world is a uniquely perfect environment for arbitrage. As William Belk argues here, the combination of it’s distributed nature, regulation, security, availability, and anonymity factors means that the marketplace has many inefficiencies, and that “arbitrage opportunities will continue indefinitely.” For example, some markets pay a premium for security, geographical location, or simply because they don’t know they can get it cheaper somewhere else. In some cases, the price discrepancies across different exchanges can be as much as 43%.
Always pay attention to Bitcoin. Most altcoins (every cryptocurrency except Bitcoin) are pegged more closely to Bitcoin than Asian currencies were to the USD during the Asian Financial Crisis. If Bitcoin price pump drastically, altcoins price can go down as people try to exit altcoins to ride the BTC profits; inversely, if Bitcoin prices dump drastically, altcoin prices can go down, too, as people exit altcoins to exchange back into fiat. The best times for altcoin growth appear when Bitcoin shows organic growth or decline, or remains stagnant in price.