New Help With TrueCrypt Encryption

Hi,

First off, I'd like to apologize, as English is not my first language.

I will be going to school soon and for the first time ever I will have to live with roommates. So I thought that it would be best to encrypt all of the data on my laptop (which is running XP) and my external hard drive. However, I do not really understand encryption all that well.

From my understanding, it basically means that whenever I come to turn my laptop on I will have to enter a password and if someone steals my laptop there is no way they can transfer my hard drive over and see what files I have.

I also know that TrueCrypt has an option to make a secondary OS, which I don't think I will need but I would like the added security.

I just don't fully understand the following: once I encrypt my laptop will any files I download or new documents I make become encrypted automatically as well? And if so, if I transfer the files to my external hard drive which I use to backup my files also be encrypted? Or would I have to encrypt those files again on my external hard drive. And I also use Dropbox often, if I upload an encrypted file, say a word document - to Dropbox can I still be able to open it and edit it?

Thank you in advance for your help. And I have searched around but I can't seem to find any clear answers about encryption and to be honest the tutorials I found for TrueCrypt were good, but I did not understand most of it, especially the terminology. So if anyone has some good links to articles that explain it clearly I'd greatly appreciate it.

Thanks again.

***EDIT***
Sorry, one more question. I will be purchasing a Mac in the next following months and was curious if I encrypt all my files on my PC and then transfer them to the Mac will the encryption remain? Or would I have to encrypt the files again on my Mac?

 

Really sorry, one last question, I promise.

If I encrypt say my resume or a photo and I email it to someone, will they be able to open it and use it as normal?

 

This link may help you understand TrueCrypt a little better:

Encrypting Using Truecrypt

 

Another link that might help.
http://www.truecrypt.org/faq

Bazza

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