Don't buy pre-ground coffee: Here's why
Beim doesn't sell pre-ground coffee. Here's why: ground coffee goes stale much more quickly than whole bean coffee. If you grind your own coffee beans, just before brewing, you're ensuring that the coffee will taste fresh. In my humble opinion, the convenience of pre-ground coffee is not worth compromising freshness. So, if you want to make the best cup of coffee possible, don't buy pre-ground, and grind your own beans!
What kind of grinder should you use? That depends on a few factors. If you're grinding for espresso, you'll need a different grind than if you're brewing drip coffee. Electric grinders are more expensive than manual grinders, but they're also much faster. If price is no object, burr grinders produce a more consistent grind than blade grinders.
If you're like most coffee drinkers, you probably don't grind your own. But if you care about freshness, it's worth the effort.