Wash the cherries and pull off the stems. Pit them with a cherry pitter, a metal straw or a chopstick.

If you're canning sour cherries, keep the pitted cherries in an anti-browning solution as you work (see notes).

Bring the water and sugar to a boil to make the syrup.

For a hot pack, add the drained cherries to the syrup and bring it back to a boil. Fill the jars with the hot cherries and syrup, leaving 1/2 inch headspace.

For a raw pack, add hot syrup to each jar (see notes), then fill the jars with drained cherries, shaking them gently so they settle. Cover with hot syrup, leaving 1/2 inch headspace.

Remove air bubbles, wipe the rims, and cap with 2 part lids to finger tight.

In a water bath canner, process hot packed pints for 15 minutes, hot packed quarts for 20 minutes, and raw packed pints or quarts for 25 minutes, adjusting for altitude (see notes).

For a water bath canner, turn off the heat, take off the canner lid, and let the jars rest 5 minutes before lifting them out.

In a pressure canner, vent steam for 10 minutes, then process hot packed pints for 8 minutes, and hot packed quarts or raw packed pints or quarts for 10 minutes, at 6 lbs in a dial gauge canner or 5 lbs in a weighted gauge canner, adjusting for altitude (see notes).

For a pressure canner, turn off the heat and let it return to zero pressure on its own. Wait 5 minutes, take off the lid, and leave the jars in the canner 10 minutes before lifting them out.

Cool the jars on a towel, not touching, for 24 hours, then check the seals. Refrigerate any jar that didn't seal. Store sealed jars in a cool, dark place for up to 18 months.