Tide.up.zip ... — File:

Automatically identifies and labels the maximum and minimum sea level values on the displayed marigram. Other Potential Interpretations

Allows users to measure wave amplitude and period or remove tidal signals from the time series. File: Tide.Up.zip ...

Instruction of Tide Tool for Windows

Depending on where you encountered the file, it could also relate to: Automatically identifies and labels the maximum and minimum