The early test operations were conducted as part of a test series, a large scale operation where many scientists, support technicians, military personnel, etc. assemble in order to set off and observe a number of devices over several weeks or months. This test series has another code name. For example the second and third test explosions of nuclear weapons (which were the fourth and fifth nuclear explosions of course) were part of the Crossroads test series. The two tests were designated Able and Baker. Sometimes the U.S. conducted two sequences of tests for different purposes jointly as a single series. When this occurred the name for each sequence was combined to form the name of the entire series (e.g. Tumbler-Snapper).

In the early test series, the same test names were reused several times. Thus there was an Able test in the Crossroads, Ranger, Buster-Jangle, and Tumbler-Snapper test series. To unambiguously identify each test the convention is to list the series code name, followed by the test name: Crossroads Able, Ranger Able, and so on. After mid-1952 unique test names began to be used, so that this convention was no longer strictly necessary. However it is useful to specify the series as well, so I have adopted the general practice of identifying tests by the series-test combination.

After 1961 the test series system was dropped as underground testing in Nevada became routine, all of which are usually considered part of the Nevada Series. Actually these tests are also still designated as being part of specific test series, but now each "series" simply corresponds to a government fiscal year (Operation Niblick is FY64, Operation Whetstone is FY65, etc.) and loses any real meaning. There was a final series of open air testing in the Pacific (the Pacific Series: Dominic I and Dominic II)in 1962, and a few special test programs (Plowshare, Vela Uniform Seismic Detonation). For Nevada Series tests after 1961, and all U.S. tests after 1963, I often follow the common practice of simply identifying them by their test names.

The code names of the actual devices are generally not well known. Many remained classified until recently (or still are). Since a bomb can only be tested once, identifying the device by the test in which it was detonated is unambiguous. In the open literature the test name has usually been used to designate the bomb that was tested, a convention followed here as well.

British tests follow a similar nomenclature but are not as systematic. Except for the first test (Hurricane), each test has both a series and test identifier. Sometimes the test identifier alone is unique, sometimes not. A variety of test series qualifiers may be attached to the series name (different from the actual test name), but the pattern for doing so is unclear. For example the Grapple series included the test Grapple 1/Short Granite (with Grapple 1 by itself uniquely identifying the test), but multiple tests all with the series designation Grapple Z. As with U.S. tests, both full series and test name designations will be given.

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