Reading a few investment books

After reading a few investment books, you decide to take the plunge and start investing in a few securities, bonds, etc. However, you realize that an emergency fund is needed before you take the next step into investing. What is an emergency fund and what should it be used for? How much will you set aside for the emergency fund? Why did you choose this amount? Your journal entry must be at least 200 words in length. No references or citations are necessary.