Hi! I'm glad to start my first post here, at Steemit. So i decide to introduce to you, cryptofans, some my favourite websites or links, that can help in bitcoin or altcoin trading. I decide to not include coin exchanges here at this moment.

1. https://bitcointalk.org - the most important websource in cryptoworld. I think, all of you guys have account there (or even more than one account :))
2. https://blockchain.info - i always prefer this one for checking BTC stats, how much confirmations for transactions, how much money investors send to ICO's (hehe )).
3. http://coinmarketcap.com/ - this is really useful website, profit traders must use this for checking capitalisation or money supply for any old or new cryptocoin. This stats will help you to predict altcoins trends, especially when Bitcoin have very volatile price in longterm. Also Coinmarketcap helps to see quickly block-explorer for some coin and check it for huge premine. It's first thing to filter fresh crypto projects and detect scam devs. Website helps you understand when coin is too cheap (low marketcap, oversold) or overbought (like hype). For better understanding you just compare projects - how much they gather investors, miners, Btalk visits at ANN thread or generated wallets, active users (this info is not published , you must analyze personally).
4. https://www.worldcoinindex.com/ - good analog of coinmarketcap analytics. Some new coins you can see here, but i like sometimes to check some altcoins charts. They are more accurate and it is very important for marketcap analysis, especially it can help to see beginning uptrend.
5. http://coincap.io/ - one more analog marketcap site for altcoins charts. This one is helpful to see actual price for hundreds alts in USD. Maybe it's easiest way to analyze information of cryptoworld, because you just need to click the most popular and huge projects on a one page. It would save your time. And time is money! 

PS. Protip - If you are russian-speaking user, maybe you also know and use Webmoney Bitcoins (WMX). So it is easy to check actual price there - http://wbtools.ru/?allr=33

This is just beginning, so if this post gather a lot of interest steemiters i'll try prepare new interesting links with my recommendations ;) Have a nice day!