Sometime you are working on a technology for a long time but you still feel difficult to explain in a non-technical way or in simple words. Same case is with SharePoint, SharePoint is not simple thing. SharePoint is not a program, it is platform, it is collection of programs. Learning SharePoint is learning like MS Office. You don’t learn one product you learn whole package i.e. MS Word, PowerPoint, Excel, Access so on.
What does SharePoint do, it makes websites. For every purpose you can create a website. It is a massive website build engine. SharePoint helps to collaborate your work with other team members, not only within your organisation but also outside the organisation.