One of the big shifts that has taken place in the way people communicate is via social networks. Social networks are becoming a major part of the way businesses work.Yammer is a mature enterprise social network specially designed to help employees stay connected with each other within a company.It has both free and standalone versions, but it gains much more functionality when enabled as part of all Office 365 subscriptions. Social networks inside the enterprise are not something to be feared; they are a new tool that will increase the productivity of all of us and make us feel much more engaged in our work.

Yammer provides a news feed section in the middle of its page where users can post updates and comment on existing posts. It also allows for users to use hashtags to highlight a certain point or use the @ symbol to mention other people in a post and notify them of your postings. Yammer supports the concepts of dedicated groups generally designed to be focused on a certain topic so it doesn't swamp the main feed or annoy those who are not interested in that topic. Access to these groups can be restricted.These groups serve as sub-groups to the overall company news feed.

Yammer allows you to: 

• Easily collaborate with other employees regardless of location. Yammer has a familiar, easy-to-use interface that allows coworkers to share what they are working on. 
• Spread information to a wider audience. Where you may have emailed something to a handful of people in the past, sharing on Yammer allows you to extend the reach of your message to others in your organization who may find it useful. 
• Get to know your coworkers better. By using Yammer, you can quickly find topic experts and business influencers, whether they are at the next desk or across the country. 
• Build up a knowledge base of information. Anyone can refer to this information, and it grows steadily larger over time. This becomes extremely useful to new employees during onboarding. 

Yammer is very similar to Facebook in its look and feel. New posts - complete with Likes - appear on Yammer's primary screen, which is known as the News feed. Icons indicating private messages and other notifications appear in the upper left-hand corner. You can create groups, which is helpful for segregating talk that is relevant only to specific internal teams. If a group conversation eventually requires assistance from other employees, you can share it with a specific person via instant message or with a whole other group using the Update function.

Hashtags are very useful on Yammer because they help categorize your posts. Yammers robust search function digs up hashtagged posts quickly, so be sure to slap tags like #[currentyear]projections or #KeyCorporateAccount on the end of your posts for future searches.

The People Directory automatically creates a searchable database of every person enrolled in your Yammer, making it especially easy to find contact information for the people in your company. Even better, employee profiles come with a Skills section that makes it easier to search for them in the People Directory. You can also create external networks and invite non-employees (suppliers and clients, for instance) to join those networks.

Anyone can attach a file to a post in order to quickly share information without forcing recipients to slog through clogged inboxes. You can also upload files - including images and videos - to a file repository where other Yammer members can download and update them. Groups have their own separate file repositories (that augment the main one) that employees can receive automatic notifications for whenever critical files are updated.

Yammer has apps for iPhone, Android, and the Windows Phone. Compared to traditional email messaging, Yammer offers some unique benefits: 

• No fragmentation of conversations into different email threads. 
• No forwarding of emails to unknown recipients, or risk of messages falling into the wrong hands. 
• No out-of-sync replies.