Microbes are ubiquitous in our surroundings, but from a food production aspect our main concern are pathogens and indicator organisms. Pathogens are bacteria that cause people to become ill, while indicator organisms present at unsatisfactory levels indicate that hygiene is a concern and that there may be other harmful bacteria. E.coli for example is an indicator of faecal contamination. E.coli could indicate bad hygiene practices in the production area (for example not washing hands), but could also indicate transfer of faecal contaminants from the field in the case of fresh vegetables. Indicator organisms help us to identify problem areas and put steps in place to prevent reoccurrence.