Setting aside your Venmo app and the Square point-of-sale system on your iPad for just a moment, let's take a look at a nice, reliable, old-school check (that rectangular paper thing that turns into money).

You might notice there's lots of info packed onto this little thing, like the issuer's name and address, date, payment amount, bank information, account number and a whole bunch of number strings that seem completely random. That latter bit is where the ABA number and routing number come into play – turns out there's no reason to pit the ABA vs. the routing number because they're the exact same thing.

However, when terms like "ABA number," "ABA routing number," "ACH routing number" and "SWIFT number" start getting tossed around, it's easy to get confused. Luckily, it's just as easy to make sense of it all with a slightly closer look.

Why an ABA Number?

Way back in 1910, the American Bankers Association or ABA came up with a way to identify each financial institution as a means to clarify who was responsible for all those checks floating around. They called it the ABA number, which was originally used simply to identify the specific bank or financial institution attached to a check.

Over time – and with the advent of financial innovations like the Federal Reserve System, magnetic ink character recognition and the Expedited Funds Availability Act – the ABA number evolved into a code that serves to designate participants in online banking, wire transfers and electronic funds transfer. That's where we are today and where the "routing number" part comes in.

The ABA Routing Number

Once the ABA number became focused on electronic and online money routing, its name became a bit of a mess. You'll hear it referred to interchangeably as a plain old ABA number, a routing transit number or RTN, routing transfer number, check routing number or an ABA routing number – they all mean the same thing. No matter what you call it, this is the number that identifies the financial institution upon which a payment is drawn when making online funds transfers. That's why you'll often be asked for this routing number when filling out forms for a direct deposit or direct payment system. Only federal and state-chartered financial institutions eligible to maintain an account at a Federal Reserve Bank are issued an ABA routing number.

Nowadays, the ABA number on a check is the nine-digit number usually located in the bottom left-hand side of the document, bracketed in between two "|:" symbols. It's followed by the account number and the check number. You can also get the ABA routing number by giving your bank a call or logging into your online checking system and peeking at your account info.

The Transit ABA Number

As if things weren't confusing enough already, the transit ABA number is also known as the ACH or Automated Clearing House number – not to be confused with an ABA number or a routing transit number, which are the same thing. Whew.

This is basically a routing number that's used specifically for the Automated Clearing House network's delivery systems. On a check, it usually appears above the ABA routing number or "memo" line in small print following the text "ACH R/T."

What About the SWIFT Number?

Mercifully, the SWIFT number has a completely distinct name from all those other too-similar numbers, but you'll often hear it grouped among them.

When banks, financial institutions and corporations transfer money internationally, they use a system managed by the Society for Worldwide Interbank Financial Telecommunications or SWIFT, a co-op of nearly 11,000 banks and companies from more than 200 countries across the globe. The SWIFT code is a multipurpose 11-digit alphanumeric number; all in one code, it identifies where the transfer comes from, where it's going and its means of transfer. That's because it combines elements like bank codes, country and other location codes and even individual branch codes into one condensed, super-handy number.