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It is not the same as Trezor or Ledger Nano since your seed is entered online (hot storage - bad) and therefore is not as secure since the seed could be intercepted. This is not likely as long as you're on a SSL (and not on public WiFi!) but using a hardware wallet such as Trezor or Ledger Nano S prevents this security hole. The main point of the these hardware wallet is exactly that... your private key is never, ever connected to the internet (cold storage - good). Since there are now over 800 cryptos I don't think Electrum stores every one of them but it does store all the major currencies. The key point of this post being about bitcoin forks, I think Electrum covers that well. Or you could even do a simple wallet holding your seed/private bitcoin keys yourself on paper -- just don't lose it ;)

@sky77, your answer is substantially inaccurate, because Electrum is a wallet that supports Trezor hardware generated keys.

However, @queeneleanor, Electrum is a Bitcoin only wallet. You can use the Trezor online wallet for Bitcoin, Bitcoin Cash, Ethereum and various ERC-20 tokens, which most of the ICO coins are. As long as you are using it with the Trezor, you are 99% safe.

This article goes into detail as well:
Why the $BCC Fork Will Cause a Short Squeeze in Bitcoin That Affects You

Ok great. I was wrong about Electrum compromising your private key. What's the value of using Electrum with Trezor? Where's the value beyond Trezor's own Bitcoin app? Also, ERC-20 token support is available in Trezor 1.5.0 firmware in conjunction with MyEtherWallet.