If someone asked this question then there is no one answer for this. SharePoint is a very big system and has plenty of features. So, if we start talking about them then it will take weeks to cover all features.
But in simple words "Microsoft SharePoint is an enterprise collaboration and content management platform which enables users to connect each other and share the information across an organization. Indirectly which solves the problems in an organization to share the documents, security, business process, maintaining data etc. SharePoint 2010 has rich UI and plenty of features."
SharePoint core features:
1. Sites: You can create a web site in seconds from the UI. You can create how many sites you want according to requirements and set the different permissions for each site. SharePoint 2010 comes with rich UI and many improvements to the HTLM as well. They have replaced all HTML Tables [in SharePoint 2007] with HTML Div tags [in SharePoint 2010]. This makes huge difference in rendering of HTML on browser both in performance and time.
And the main important thing is Ribbon. The Ribbon is big revolution and all the options are one the page itself. The Ribbon properties change dynamically/automatically depends on what context you are in. There is no need to leave the current page and do something. Everything on the page and do the stuff needed. With this rich UI and ribbon support it is very easy to create and manage content in the site.
SharePoint 2010 sites can be browsable on any browser. Only limitation is it will not support IE6 [I believe no one is using IE6 still]. So, we can call it as Multi-Platform. This will be very good for developers and users that they have their own impression on browser usage. I like IE9 and Mozilla. Earlier version of SharePoint don't like browsers other than IE. So, this problem is resolved in this version.
SharePoint 2010 supports Cloud computing as well. So, you can host it general environment or the cloud computing environment to give access to internet users. This is again a major feature included in SharePoint 2010.
2. Communities:It is more of Social connections. You can connect to employee [colleague] or users through user profiles , my sites and people search. This way you are connected with others and share information very easily. Another thing in communities section is "Informal Knowledge". This includes tagging, rating and feedback features. For example, many users are searching for a common document then what we could do is, tag that document with relative keywords. So that it will come up in top search results. This way users get whatever they want very easily. Another option is rating. You can give rating to particular document or item.
3. Content: As we discussed in earlier sections now with SharePoint 2010 creating or managing content is very easy with the new rich UI and ribbon. This is very easy for admins to find the content in the site and make changes. You may feel that this is same as editing MS Office files like word, power point in browser. SharePoint 2010 manages huge and complex Metadata across site collections very easily.
4. Search: Huhh!!! It is a very big improvement in SharePoint 2010 compared to previous version. The way the search improved is unbelievable and gives the exact search results what user is looking for. There are many ways how they improved search. Here are the main things:
- Improved relevancy: When user is typing the search word SharePoint detects what user is trying to search for and gives exact result they are looking for.
- Refinement & Related Searches: For each search word given it searches for the related keywords as well and give in the result set. If you search for John then it gives search results which has John on top and then Jon, Don etc after it. Because Jon matches with 3 letters Don matches 2 letters etc.
- Wildcard search: This is what already known thing and not really need any special explanation.
5. Insights: This mainly covers the business process in an organization. The perfect implementation to this is workflows. SharePoint designer workflows improved and added many activities to the 2007 designer activities. With these we can solve many problems without writing custom code. And by writing custom code you can create your own activities easily. Along with these there are improvements to the excel services and charts. In this version of SharePoint they integrated Visio services. You can create a workflow in Visio and import them to SharePoint directly. It is one of the fantastic feature in this new version. The main advantage is who is good in Visio [I mean a common person] also has option to do some stuff which will be useful in SharePoint.
6. Composites: This concept comes from the Mash-Ups. Pulling information from different data sources and combining it single place. So, we can achieve this in 4 different ways:
- SharePoint designer 2010
- Infopath 2010
- Business Connectivity Services [BCS]
- Access Services
So, finally in simple words we can say SharePoint is:
- Quickly create and manage content in your organization
- Collaborate in new and easy ways through social capabilities
- Search helps to find easy and relevant content
- Streamline the business process in organization
- Visualize the information or huge data
For complete idea please take a look at this nice video.
I believe you understood briefly What is SharePoint. Before we end this concept lastly I want to mention, SharePoint 2010 is only supports 64-bit. [There is no 32-bit anymore. ]So, all the infrastructure and the software like [Windows Server 2008, Sql Server etc] should be 64-bit.