The SWSS file extension is associated with ClarisWorks.
How to open:
You will need a spreadsheet program with support for a specific file format in order to open your spreadsheets. Nevertheless, most non-proprietary formats are well-supported in modern spreadsheets programs.For general information please read:Basic info how to open spreadsheet files
How to convert:
Spreadsheets can be usually converted between various formats, or the data can be extracted and saved in structured text files, such as CSV (Comma Separated Value). Sometimes, export to a generatic database format is also possible.
For general information please read:Basic info how to convert spreadsheet files