Calculators evolve and often follow one another following technological improvements that make a new model replace another with more features.
(or to correct a major defect of the previous version)
But sometimes, rather often in the history of Texas Instruments calculators, a model is declined in several identical models without any technological change.

either for purely commercial reasons a calculator will not have the same name from one country to another,

either for reasons of change of production site a calculator will not have the same visual identification,

or sometimes without really known reasons (to wonder if, even at Texas Instruments, anyone knew the reasons ...).

Listed here are the examples of "lookalikes" that I have personally observed either by having acquired different versions of the same calculator, or by having participated in auctions to try to acquire a version of a calculator that I did not own.
Another calculator, the famous TI-88, seems to have existed in prototype form in several versions... But unfortunately I've never seen one in real life...
only in photo!

For the evolution, following a defect, the most notorious case is that of the first generation of "slanted" whose defective keyboard has led to a new generation of "slanted" calculators with a corrected keyboard.
So the BA-55 became the BA-54, the TI-57 LCD became the TI-57 II, the TI-55 II became the TI-55 III...

The first example of a purely commercial reason is the calculator named The MBA in the USA which was released in Europe under the name TI-42 MBA.
(The first was assembled in the USA from 1977, the second was produced in Italy from 1978.)

But there was also the TI-55 which became TI-51 III in Europe.
(The first was assembled in the USA from 1977, the second was produced in Italy from 1977.)

The SR-56 had two very slightly different presentations :

on the version assembled in Italy from 1977 the name "SR-56" appears alone,

on the version produced in the USA from 1977 the name "SR-56" is accompanied by the mention "Programmable".

The TI-57 also had two very slightly different presentations :

on the first version, assembled in Italy from 1977, the text "Texas Instruments" and the logo are printed on a metal plate stuck on the TI-57,

on the second, produced in Italy from 1978, the text "Texas Instruments" and the logo are embossed in plastic directly on the TI-57.

The TI-53 was first released in a "slimline" version produced in Italy in 1978.
Then in 1985, a first TI-53 in "slanted" version was produced in Italy with the Texas Instruments bottom left.
Finally in 1986, a second TI-53 "slanted" still produced in Italy had the logo Texas Instruments top right.

The TI-56 will be the European version of the TI-55 III but there the problem will be more complex since there will be several TI-55 III and several TI-56 with different visual identifications, and sometimes even color changes...

The TI-56 exists in three versions ... absolutely identical in functionality, but just different by the wording and position of the Texas Instruments logo.

The TI-55 III also exists in three versions ... also absolutely identical in functionality, but also just different by the wording and position of the Texas Instruments logo.

The TI-57 II also exists in three versions ... also absolutely identical in functionality, but also just different by the wording and position of the Texas Instruments logo.

For the TI-57 LCD, an European version will differ from the US version : the calculator is the same, with the same name, but the colors are different.

La TI-60 will be released in two versions :

one with the inscription "ADVANCED SCIENTIFIC" made in Italy in 1986,

one with the inscription "PROGRAMMABLE SCIENTIFIC" made in Italy in 1990.

The TI-68 will be manufactured in three different forms :

the first in metal produced in Italy from 1989,

the second, in plastic, produced in Italy from 1990,

the third, in plastic, produced in China from 1995.

Apart from the choice of materials (for economic reasons ?) which differs from one to the other, the inscriptions will be modified as well as the ON / OFF button.

(Note : the presence and then the absence of screws at the back of the calculator depending on the version and larger characters on the keys of the third)

The TI-62 exists in two versions :

one, the most common, with white number keys,

the other, rarer, with yellow number keys.

The TI-67 is available in two versions:

one, the most common, with a gray display,

the other, rarer, with a yellow display.

The TI-84 Pocket was released in two versions:

the first in France, dark gray released under the name of TI-84 Pocket.fr in 2011,

the second in Asia, light gray released as TI-84 Plus Pocket SE in 2012.
The Asian version is mainly on sale today in India and Singapore.

For the replication of calculators in different colors, graphing calculators have not been forgotten...

Texas Instruments launched the "Back-to-School" campaign in 2001 with the introduction of the TI-83 Plus< /B> in a translucent blue design.
This approach was successful and from there other calculators were released in specific colorful designs for each retailer.

The first reseller, in 2001, was Target followed from 2003 by Walmart then < I>Staples (2004), Office Depot (2007), Best Buy (2008), Office Max (2008) ... Amazon (2017)

From the translucent blue TI-83 Plus to the TI-84 Plus CE Python Measure Mint and the TI-84 Plus SE Raspberry , TI-84 Plus SE Blaze and the multiple different TI-84 Plus SE Pink, there is something in these series that will drive a collector crazy!
(It is almost impossible to count all the worldwide variants of TI-84 Plus...)

Even for the most recent, the TI-Nspire CX II (from 2019), versions exist depending on the market: USA, < b>Europe and China.
There is also a yellow "School Property" version as for the TI-84 Plus, TI-84 Plus SE, TI- 84 Plus C SE, TI-Nspire... Version known as "EZ-Spot".