This comment expressing confusion on this valiantly misguided OP seems like a good place to throw my standard explanation out into the aether to do neither readers nor myself any good.

A transaction has two polarities, because it represents a flow of value. The credit side is the source, the debit side is the sink/destination/whatever. Let's temporarily pretend that every transaction hits exactly two accounts for the moment (which is not true), to make it easier.

Let's say we have $1000 in Cash, which is an Asset, and we want to buy a Pizza, which is also an Asset, for $20. How does this look in accounting?

Cash provides the source side, and Pizza provides the sink. Cash is credited $20, and Pizza is debited $20. If we ran the balances now, Cash would come out to $980, and Pizza would come out to $20.

Let's unwind that transaction. We're a business; we don't trade cash for pizzas. We contract for delivery of pizzas with a pizza vendor, who invoices us.

So here we are, with $1000 in Cash and $0 worth of Pizza. The pizza delivery driver comes, and hands us a pizza and an invoice. We know we have to debit Pizza $20; what is the credit source for this debit? Well, the pizza vendor has actually extended us a loan worth $20, in a sense (this is called "trade credit"), and the offsetting entry is the fact that we owe the vendor $20, as memorialized in its invoice. This goes in a Liability account, usually called something like Accounts Payable.

Current balances (if we ran them - "running the balances" is thought of by accountants as a discrete operation, just FYI):

Assets/Cash $1000
Assets/Pizza $20
Liabilities/Accounts Payable $20

Accountants think of accounts as being naturally debit-increased, like Assets, or naturally credit-increased, like Liabilities. I find it a bit misleading to try to think of these as positive or negative signs, as you might be inclined to at this point. It's just $20 - don't even think of it as cr $20, IMO. (dr and cr are the abbreviations for debit and credit.)

Let's just leave that on the books and eat the pizza. After eating the pizza, we no longer have $20 worth of pizza, so we have to credit Assets/Pizza $20. What do we debit to offset this - i.e., where did the pizza value flow to? In this case, it would be a Depreciation account (these are debit-increased) - something like Depreciation/Eaten Pizzas. So we have:

Assets/Cash $1000
Assets/Pizza $0
Depreciation/Eaten Pizzas $20
Liabilities/Accounts Payable $20

(a commenter below points out correctly that this would be an Expense, not a Depreciation, and I'm still in the edit window!)

Meanwhile, someone pays us on one of our invoices, which we had sent out earlier offscreen. When we delivered our fine $50 widget and invoiced the buyer, we entered that into our accounting system as a debit of $50 to Assets/Accounts Receivable, and a credit of $50 to Assets/Widgets. This part of the system looks like (we still have 9 widgets in stock):

Assets/Cash $1000
Assets/Widgets $450
Assets/Accounts Receivable $50

But now that the invoice is paid, $50 of value flows from our receivables asset into our cash asset - i.e., we credit A. R. $50, and debit cash $50. Getting paid is nice.

Assets/Cash $1050
Assets/Widgets $450
Assets/Accounts Receivable $0

After the customarily long delay, our accounts payable department has approved payment of the pizza invoice. Cash has to be credited, because cash is flowing out, and it's probably easy to guess the debit where it goes to - that's right, our Liabilities/Accounts Payable is finally cleared, because we don't owe the pizza vendor $20 anymore.

Assets/Cash $1030
Assets/Pizza $0
Assets/Widgets $450
Assets/Accounts Receivable $0
Depreciation/Eaten Pizzas $20
Liabilities/Accounts Payable $0

Hope that makes sense. It gets more complicated in real life. Accounting is nontrivial. If there are any accountants in the thread, maybe they can correct any errors I've made.