Summarize this article in one sentence.
Typically, super-automatic machines come with their own grinder. If your model does not have a grinder, make sure you invest in one alongside your machine. After all, you will need it to make your espresso! A quality grinder is a necessity when properly preparing espresso for extraction.  Choose a grinder in your budget, as they can get very expensive. When selecting a quality grinder, look for either step-less or stepped grinders. The stepped grinders have separate settings for fine to coarse grinding. Step-less has no pre-set settings, and you can grind the beans as fine as desired. If you don’t want to drink straight espresso, look for a steam wand when selecting your espresso machine. These are metal stems that are usually located towards the side. There is a bit of a learning curve with steam wands, but with some practice you can easily use them to create voluminous milk foam.  To use, first fill up your pitcher with cold milk. Submerge the tip of the wand just below the surface of the milk, and angle your pitcher. Let a small bit of air into your milk, then let the milk heat up to the correct temperature.  These work great when creating lattes and cappuccinos, for example. Steam wands can be slightly difficult to clean, so make sure you wipe down the wand after each use. Many espresso machines come with a built-in frothing option. With a push of a button, these devices heat up automatically and mix your milk instantaneously. This is the most convenient method to make frothy espresso drinks. Many of these models also offer a large, removable milk tank. You can easily pop this in the fridge instead of cleaning it after each use. If you want to make foamy espresso beverages but the espresso machine you are interested in doesn’t have this feature, that’s okay! You can always purchase a separate milk frother. These effortlessly make your foam, but they can have slightly inconsistent results.  To use, fill the internal tank with your milk, and select the froth button. Some machines have settings to simply heat the milk instead of frothing it. Then, in about 30-60 seconds, your milk will be whipped and foamy.  These are not the best for creating luscious, extra frothy beverages. If you are an espresso aficionado and want to invest in a professional system, go with a dual boiler. These have a separate tank for brewing your espresso and steaming your milk, as opposed to single boiler systems which require you to wait for the machine to calibrate between brewing and steaming. The faster you add milk to the espresso, the better and fresher the drink tastes.  Most single boiler systems require the machine to make the espresso shot, turn up the heat to make the steam, then steam the milk. Dual boiler systems complete both of these functions simultaneously. Go with this machine if you want to serve espresso in a coffee shop, for example.

Summary:
Get a grinder if your machine does not have a built-in option. Get a machine with a steam wand if you want to create milk foam. Go with a machine with an automatic frother to easily prepare your milk. Use a stand-alone frother if your machine doesn't have a frothing option. Choose a dual boiler system if you want a professional machine.