If you're starting a small business, or you already run one, you'll need some software to help you keep track of everything. You'll certainly need something to help with accounts and invoicing, and possibly some sort of CRM (customer relationship management) system to record details of leads, prospects, customers, potential orders, and so on.
If you've never used such software before, and you want to see how it all works, check out Soho OS. It's an online service, aimed at small businesses, that provides cloud-based accounting, CRM and other services. A basic account is free, and provides pretty much everything you need to get started.
You can reach the site at www.sohoos.com. All you need is a web browser and an internet connection.
As to whether you continue to use the service in anger, and whether you think that trusting all your critical business data to the cloud, is a good idea in the long term, that's a decision that only you can make.