There's terminology all over the place on how to fill jars and how to run canners. Let's go over the definition of each and why you would choose one over another. We are not going to discuss what is and isn't approved by the USDA, nor what you think is correct; Margaret. Everything heats to the proper temperature inside the canner anyway.
Cold Pack - This is my method of choice. Anytime I can work with product that isn't scorching hot is a plus. I'm a natural born klutz and this keeps my toes and titties out of hot water; literally. Cold pack simply means that you're adding product to the jar that is room temperature or colder.
Hot Pack - I use this method when doing jams/jellies and not much else. You're going to be dipping up and filling jars with hot, usually boiling product and you're probably going to get burned. Sometimes it's a necessary evil.
Dry Pack - This is most useful for potatoes, par-cooked hamburger, ugly chicken; etc. This simply means that you pack the product into the jar and don't add any additional liquid. It can yield some exceptional results.
Wet Pack - You add liquid when you're packing the jars. Sometimes it's in the form of a fully mixed up soup. Sometimes you pack a jar with fruit and pour syrup over.
Cold/Cold/Cold - This means that you start with cold jars, cold product and a cold canner. I use this method alot. Again, everything has to heat to temp inside the canner before it can boil and/or come up to pressure. It's the heat that kills the germies; Margaret.
Dry Canning - This refers to packing dry ingredients like pasta, beans, flour, etc. into jars, placing into the oven to heat and adding lids and rings for them to seal. (This process doesn't work for me, I'm too slow on the lids.) I also use this to describe vacuum sealing dry products in jars.
Open Kettle - Refers to folks having hot jars, hot product, hot lids and rings; then filling the jars, capping right away and allowing the jar to seal. This is used commonly for pickles or jams/jellies. (This process also does not work for me, too slow to keep everything hot/hot/hot.)
Oven Canning - Folks heat the jars full of product up inside the oven, add the hot lids and rings and allow the jars to seal. Some folks are even using this in place of items that really should be pressure canned.
Some of these terms seem interchangable and it's sooo easy to mix them up. Hope this helps sort out some of the "clear as mud" recipes and comments you will see online.