how do I assign categories to data cells?

I have a calc spreadsheet which lists payees/expenses/sources in cells in one column. I would like to assign this data to another column to auto-list its category (created by the user.) So that if I enter the name of my utility company as the payee/expense that this name would auto-populate a relative cell with category ‘utility.’ How do I set this up?

You may wish to reconsider your approach to how to best solve this question. While spreadsheets have a degree of database functionality, your question implies that a database (such as Base or MySQL), may be more appropriate approach. Either-way, you will need research how this can be accomplished.