Score prioritize and dedupe leads based on your own criteria to make sure you only get in contact with the highest probability leads at a given company.
When sending emails to potential customers you may have 10 or more contacts at a given company but you don't want to email all of them. To keep the sales process working effectively you probably only want to email the top few contacts at each company based on lead scoring metrics.
Use a "Scoring" object to add scoring rules for each attribute you're interested in. You can make as many rules as you want each searching for a keyword in a given column and assigning an applicable score. You can then use sort and dedupe objects to reduce your list to only the top scored leads from each company.