German and English belong to the same language families, this means they descend from a common language. Not to mention the many words both languages borrowed from Latin.
Therefore is normal they have many words that are similar in spelling and in meaning (real friends). Unfortunately, there are also a bunch of words that despite being spelled or pronounced similarly have a completely different meaning. Those words are know as false friends.
For example, in German the word fast means almost, in English the word fast means quick.
False friend can be very dangerous as much as human false friends, as you can see in the example in the strip below.
In this post we focus only on false friends, but there are also many real friends, as mentioned. Those words are really really helpful for those learning German.