The introduction is the part of the essay where the reader gets sucked into the writing. It is a very important part for several different reasons. This is where you learn the topic and get some key information as well. Essays without introductions would be messy and confusing for everyone. If you do it poorly it can be just as bad. You have to learn how to write one the proper way. Here are some tips to show what to include in a proper introduction.
When writing the first paragraph you have to really introduce the topic you are writing about. That is most of the point of this paragraph and its namesake so it should be introduced properly. Make it clear what the essay will be about right there in that first paragraph. If you are not clear, then the reader gets confused and might give up all together. So be clear and describe the topic briefly in your own words.
This is also where you should explain what the paper is about. Give them a short summary of what the paper as a whole will say, do or prove to them by the end of it. This summary allows them to connect with what they are about to read and help them better understand and follow your essay. For example, you want to give them a taste without giving away your whole essay making reading the rest redundant, you just want to tell them a little about it.
If the introduction is dry and boring, then the reader is less likely to want to read further. When the reader is the person giving out your grade, you want them to want to read the whole thing. So you have to try to make it exciting and grab their attention right away from the start. For example, you could say that your paper is about the life cycle of a frog or you could aim higher and say that your paper shows how a tadpole becomes another creature entirely. See how the first sentence is plain, while the second is more exciting?
The first paragraph should tell the reader what to expect, get their attention and actually introduce a topic. This paragraph is so important because it is the first thing people read. Make it worth the time.