Greetings to everyone visiting from The SR-50 Commemorative Edition site at Datamath.org!  (My SR-50 is shown below).  Visitors: Click here to go to my main calculator page--and thanks for stopping by.

Texas Instruments SR Electronic Slide Rule Series.  Left to right:
1. SR-10: Two versions of this calculator exist; the other one has "SR-10" in the red plastic up near the LED display.
2. SR-11: This was the first TI scientific with small keys.
3. SR-16

1. SR-16-II: This one is noteworthy as the last TI scientific calculator without trig functions.
2. SR-50: The unusual styling makes this calculator a collectors' favorite.
3. SR-50A

Left to right:
1. SR-40: Later in time, though earlier in numerical sequence.
3. SR-51A
4. SR-51-II
 

Texas Instruments TI-30 series.  Still being extended.
1. TI-30: Probably the best-selling calculator ever, if legends are to be believed.  Trivia note: The TI-30 showed up on an episode of NBC-TV's Freaks and Geeks in 01999.  A couple of glaring errors found their way into the script:
        1. Despite the fact that the TI-30 was made in America, one of the characters describes it as "made in Japan", and is surprised that a calculator that says "Texas Instruments" would have such an origin.
        2. The TI-30 is described as a graphing calculator  (Millie: "It graphs and everything!")--but the show was set in 01980, fully eleven years before TI's first graphing calculator and 6 years before Casio launched the first graphing calculator.
2. TI-30X: Displaying 69 factorial--which was for years the "ultimate" number on a hand-held calculator.

1. TI-30Xa Solar
2. TI-30X IIS: Latest in the series.  The "S" denotes a solar-powered calculator; a companion model, the TI-30X IIB, uses batteries.

1. TI-31
2. TI-33: LED model manufactured and sold in Europe.

Two more TI-Euro calculators:
1. TI-45: European version of the SR-40 (above), with a blue-green LED display.
2. TI-51-III: European equivalent of the TI-55 with 32 program steps available.

1. TI-34
2. TI-54

TI Collegiate or SC-10: Notebook format.  30 of the right-side keys can be redefined with the switch in the upper right.

TI-52: A scientific calculator in the horizontal format used by TI in the late 01980's.

1. TI-60X: This calculator is scientific, but not programmable.  It's similar to the TI-68--one curious difference is that the alphanumeric keyboard only includes twelve letters of the alphabet.
2. TI-68: This pinnacle of the TI scientific line is a somewhat-scarce collectible calculator.

PC-200 printer: This thermal printer is compatible with several TI calculators from the 01980's, including the BA-55 and TI-66.   (Thanks to Jonathan Rodin for correcting this list.)