Tiny BASIC was, as its name suggests, a very small version of the BASIC language. It was not really very good for writing useful programs in because it was too limited but it was usable. Above all, it was small. This was very important when RAM was expensive. Usually there just wasn’t enough room to load a full BASIC interpreter so it was stored in ROM or EPROM. Tiny BASICS for the NASCOM-1 were available from several sources. I think that all of them were based on the original Li Chen Wang’s Palo Alto Tiny BASIC so they all looked similar, although some had useful extensions.
NASCOM sold a 2k EPROM version (called Tiny BASIC in some documentation and B-BASIC in others) and an extended version (Super Tiny BASIC). See spec sheet here (70k). I strongly suspect that both of these were written (or adapted) by Richard Beal. This would account for the alternative names.
I also have some documentation on three versions from C C SOFT. This mentions:
Level A BASIC
Interesting because it was a 2k implementation fitted instead of the monitor EPROMs so the computer always started in Tiny BASIC. It allowed 809 bytes (decimal) as program area on an unexpanded NASCOM-1!
Level B BASIC
As level A but with the addition of LOAD, DUMP, PEEK, POKE, IN, OUT and USR commands. Still 2k but loaded from tape. It appears that this could also be run from an EPROM but it used the monitor routines in NASBUG T4 or B-BUG.
Level C BASIC
This was a 4k BASIC with floating point math and many more facilities. It was also ROMable and would install on a standard RAM expansion card in four 2708 EPROMs if required.
Probably some of Tiny BASICs unpopularity was caused by its severe shortage of error messages. WHAT? meant that it didn’t know what you wanted to do, HOW? meant that it recognised the command but couldn’t do it and SORRY? meant that you had run out of memory. That was it. It didn’t make for easy program debugging.
For those of you with a particular interest (and cheap telephone bills) I have included a version of Tiny BASIC written by a member of the Merseyside Nascom User Group in the form of scanned pages from their book. tinybas
nascom.info 
