Tweetdeck is available as a browser-based tool as well as a desktop version and a Chrome app. It offers multiple columns so that you can watch multiple Twitter streams at once and to post from multiple accounts. You might have your own Twitter account(s) on display, plus a hashtag that you follow, notifications, and maybe a Twitter list as well.
Since Twitter acquired Tweetdeck, you now log in to access the service at Tweetdeck.Twitter.com, logging in with your Twitter username and password, and the help pages for Tweetdeck are part of the Twitter Help Center; you will find instructions there for how to use Tweetdeck to schedule tweets in advance, along with other special services.
Also, remember when I told you there was a trick you could use to add yourself to a list? Tweetdeck allows you to do that; here's a step by step on how to use Tweetdeck to add yourself to a list.
Hootsuite is a social media management tool that you can use with Twitter and also Facebook, plus additional social networks. When you go to Hootsuite.com you will be prompted to log in with your Twitter or Facebook for Google+ account, and then after you are logged in to the site using one of those accounts, you can integrate your other services. Like Tweetdeck, the main Hootsuite page is a dashboard allowing you to view multiple social network accounts in the different columns:
If you are just beginning to use Twitter, you probably don't feel a need for services like these, but it's good to know that they exist so that if you find yourself hampered by the basic Twitter browser options, you can choose a tool that meets your needs.
Another multiple account option: different browsers. Just speaking for myself, even as someone who uses Twitter every day, I do just fine by using Twitter in my browser without using a management tool like Tweetdeck or Hootsuite — but I do use two browsers: I manage my @OnlineCrsLady account in Chrome and my @OnlineMythIndia (class account) in Firefox. That's a good solution for me! (You'll learn more about creating a separate class Twitter account if you want in the final Stage of the Bootcamp: D2L Twitter for Your Classes.)
NEXT STEP => Next up is the super-powerful automator IFTTT which you can use for Twitter and many other Internet services besides.