This sounds like a school homework question, but I'll give you a quick starting point.
I am not an accountant, but I ran a business and had a business minor in college.
Basically cash basis means you report the cash in the fiscal year you acquired it. It doesn't matter if someone PROMISED it (by way of signing a contract or something), it only counts when it was given to you.
Alternatively you can report stuff as to when the money was "booked" - not that you've received it, but that you have a more or less official commitment to it. It could be orders from distributors, or other customers, whatever.
Depending on the nature of your business, one may be more appropriate than the other. For instance, if you have a lot of up-front expenses that go with those orders, you might want to be on a non-cash basis, so you can offset those costs against something. Otherwise you show a huge loss one year (when you make the deals, but spend the money) and a huge profit the next (when you get the money, but have already spent the up-front costs the year before). The non-cash basis lets you even it out.
Note that you can't pick and choose from year to year - you have to pick one basis and stick with it. You can change, but you need to have a good reason. The IRS will go with an occasional change, but I doubt they'll go with one every year.
Or, you could open lots of "sub-companies" to get around it; I'm sure people are doing it.
But in general, you pick the accounting method that's most appropriate to your business. As a rule, you want to pair your expenses with your profits. Sometimes that works best with a cash basis, sometimes it works best with a non-cash basis.