Gibson Office Spreadsheet Software. Written by Michael Gibson Maintaining Since 2010 Free office spreadsheet software for: - Apple Mac OS - Atari 8-bit [48k or greater required] - C64 - Linux OS - TI-99/4A [48k or greater required] - Windows Spread Sheet Software: - GSS T2 for Atari, C64, and TI-99/4A - GLASS and GSS 1.0 for Mac OS, Linux, and Windows Written in BASIC and C code. The original GSS 1.0 file format was released under the GPL 2.

.

.

.

Linux CLI GLASS - GLASS for CLI source and EXE -- Version 0.8.2 GLASS_0_8_2_oct_9_2025_Linux.tar.gz GPL3 Windows 64 CLI GLASS - GLASS for CLI source and EXE -- Version 0.9.0 GLASS_0_9_0_oct_17_2025_win32.zip GPL3 The GTK 2 GLASS Interface development is being retired. The last two GTK GLASS source files: - version 0.5.0 - gtk_intf-05-05-10-20-21.c - version 0.5.0 - readdata-05-05-10-20-21.c - Manual for Glass You can manually edit the GSS file: GSS 1 file format Test Book 1 in GSS 1.0 format. Win64 Screen shot of running book1.gss Test Book 2 in GSS 1.0 format. Win64 Screen shot of running book2.gss Linux Screen shot of running book2.gss GSS T2 file format - documents coming soon. Advantages of GSS 1 (lite) system and files? - light weight - formula standards - 93 columns, 93 rows. - General purpose SS - Scrollable text display Advantages of GSS T2 system and files? - light weight - Data Model information - 20 columns, 30 rows - Made for low resource computers. - SS aimed at financial user - Scrollable text display

.

.

.

TI-99/4A GSS requires: - 32K Expansion board or 32K Expansion side module. - TI Extented BASIC - One or more Cassette drives and/or disk drives - Currently only uses GSS T2 file format - TI-99/4A source code GSS version 0.9.25.A under GPL 3 - Oct 3 2025 - TI-99/4A screen shots.