Batchforce is used to make bulk data updates in Salesforce. Write a SOQL to retrieve data, and use an expression to transform each row as it is retrieved into the data that should be loaded back in.
It is faster than exporting all of the data, updating it in Excel, then reloading it using data loader, or writing a custom batch apex class.
Batchforce Web is a WASM application that uses the Salesforce API endpoints directly from your browser.