SYLK (Symbolic Link) is a format devised by Microsoft for data interchange between applications, primarily spreadsheets. It has nothing to do with the "symbolic links" or "symlinks" used to tie multiple file paths to a single file in some operating systems including Unix-type systems.
Some of the "boilerplate articles" on sites that claim to document file formats by extension refer to .sylk or .silk files, but the official extension of this format is .slk (still under the influence of old-timey DOS thinking where extensions had to be 3 characters or less).
- The first record must be an ID record.
- The file must close with an E record.
- All record and field codes must be entered in upper-case letters.
- Record and field type are separated by a semicolon.
- Each record must be terminated by CR/LF.
- There must be no CR/LF characters within a record or field.
- D and G records always relate to the last C command.
- When using NE records, the file name must be defined beforehand using NU.
- The dimensions and subdivision of the window must be defined in logically ascending sequence.