Just a super efficient way to quickly connect with co-workers and business partners! Skype for Business is IM, calling, video calling, and sharing and collaboration all rolled into one package.
Here's what the main page of the app looks like. (Want to learn how to add a contact?)
When you hover over a contact's picture, a quick menu appears.

If you click the IM button, you'll get the conversation window.
TIP You can also just double-click a contact's picture to open the conversation window and start an IM.
Here's what the conversation (IM) window looks like. (Want to learn how to send an IM?)
And here's what the meeting window looks like. (Want to learn how to share your desktop or a program?)

More please...
The Skype for Business UI is pretty intuitive, so playing around with the app is a fun way to learn. Want more? Here are some help topics to get you started.
Add a contact in Skype for Business
Send an IM in Skype for Business
Make and receive calls using Skype for Business
Set up a Skype for Business meeting in Outlook
Share your desktop or a program in Skype for Business
Set up and test Skype for Business audio
See Also
Quick Start Guides about Skype for Business
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