Calories - how do you count?

Calories are on all food items. How do you count them? Many people forget that the calorie count is usually per serving. So, if one serving (probably a few ounzes) has 300 calories and you have 2 servings, you are already into 600 calories.

A woman needs about 2,100 calories, ie. on an average. Say you have one bagel for breakfast, then a lunch (sandwich and salad) then a hearty dinner. Don't you think that could amount to at least 3,000 calories? Oh, don't forget the cream cheese and salad dressing!