Pasteurize
Pasteurization is the heating of a product (milk...) at 62.8°C for half an hour, or 15 seconds at 72.8°C. This will largely slain the bacteria, but not the spores of bacteria. Due to the short duration and low temperature, structure and flavor remain largely retained.

Sterilize
is based on the killing of bacteria by strong heating usually between 90 and 120°C. So you have the foods expose to high temperature followed by an airtight seal. Meanwhile you prevent that new bacteria join your food. Sterilization is usually done in preserving jars or jars with screw cap. In a boiler or furnace you bring the food in the closed pot over the boiling point. Then they keep almost indefinitely.
Dry the rim of the glass completely, close the jar and place the clamp on it. Touch the rubber rings as little as possible.

There are pliers to get recalcitrant screw caps loose. No idea why these bitches are sold that expensive. I found in the auto shop a grab to turn loose oil filters for 1/3rd of the price. Works equally well or better.

For vegetables boiling for 1 hour at 100 degrees is usually sufficient. Beans and carrots should first blanch some minutes. Also tomatoes, courgettes (zicchini) and pumpkins can be processed as puree.

Fruit
such as raspberries, strawberries and pears you cover first with a sugar syrup. Fruit is pasteurized rather than sterilized. That is to say that the fruit, with the exception for pears, never is heated higher than 75 to 80°C. Fruit can pasteurize in own juice with sugar or sugar syrup. The amount of sugar varies from 300 to 500 grams of sugar for 1 liter of water for 1 kg of fresh fruit, to 1 kg of sugar for 1 liter of water on sour fruit.

Clean the fruit and bring them in cleare jars. Pour over the cooled sugar water and go on the same way as employed for sterilizing vegetables. Allow 20 to 30 minutes pasteurize at between 75 and 80°C. It is sufficient that the sugar in the water boils and then cools.

You can also sterilize meat. For meat and hard tubers you can subtract the time of sterilizing in advance of the cooking time: so searing or light cooking, light spices, put and undercooked in the jars an sterilize.