Skype for Business (formerly Lync), now part of Microsoft Teams

It is a very simple messaging and video meetings tool

The basics of Skype are easy to use (i.e. sending an IM, adding a Skype meeting to a meeting, presenting your desktop). However, Skype is just too far behind competitors in terms of functionality. It is very basic, and doesn't offer the same functionality as other tools like multiple audience types, organizers vs. presenters, Q&A, Polling, etc.

Skype for Business is a tool that works very well with the Windows platform in all its functions. It is a good tool when you are on the move and you don't have a computer to connect with. Calls and video calls can quickly download internet traffic if this is limited by the telephone operator; so it is better to limit yourself to chats and, if you really can not make calls with the normal SIM, you can call, but for a limited time.

It is a good tool and connects to other Microsoft applications well. But problems with Skype Meetings (mainly sound), slowness (for 2019), and arguably better-competing applications do not allow me to give it a higher grade.

Skype for Business is very easy to use. It does what you expect, and it does it very well. No training is required for staff.

It's an easy and intuitive program. There isn't anything complicated about it. It's even easy to transfer phone calls.

Skype for Business is fairly user-friendly and has a good UI. It has strong audio and video conference call capabilities. It's easy to conduct meetings with various stakeholders across different locations and timezones. The chat and share a file or share my screen functions work seamlessly. If your company uses Office 365, then I would highly recommend it.

As I wrote before, I think is an easy-to-download tool that doesn't require much system/hardware specifications, but also it doesn't work properly in cases of bad internet connection. Also, I think it needs to be more intuitive when it comes to fixing sound and microphone problems, because once you enter the call, if you didn't allow Skype for Business to access to your microphone (by mistake), for example, then you don't have the possibility to change it, so you have to leave the meeting and rejoin to fix the problem.

Stability is too inconsistent.

Skype for Business is great for instant messaging, with some minor issues. It has an acceptable quality for audio and video conferencing. Its integration with Microsoft Office is a big plus.
The one that is a real setback is the screen sharing during conferences, which can be really annoying to watch if it doesn't disconnect too often.

Skype is pretty straightforward.

I use it daily to communicate with my team.

I find it very easy to use and easy to operate. It is definitely easy to get used to and from a user perspective is a solid product. I also find it to be very handy and useful for a small-mid-sized org like ours. It is easy to communicate effectively and get information quickly.

Usability is great. Everyone in the organization can use basic chat functions and other features (like video conference, and screen share,) enhance the products capabilities.