The natural successor to TrueCrypt (unless the guys at TCNext can come up with something better) is VeraCrypt. The (French) developer took TrueCrypt's code and fixed the weaknesses found during the security audit performed on TC. The main enhancements and corrections done so far are listed on this post.
VeraCrypt's dev is also very active on the TCNext forums with the username IDRIX, and unlike the devs of TC, who never revealed their identities, he isn't afraid to reveal his real name, picture and personal info. On this topic, he answers lots of questions related to VeraCrypt.
The second free and open source alternative I'd recommend is DiskCryptor. It's main drawback is that, unlike TrueCrypt and VeraCrypt, it's only available for Windows. Also, it's developed by anonymous Russians, so there's that.
VeraCrypt's dev is also very active on the TCNext forums with the username IDRIX, and unlike the devs of TC, who never revealed their identities, he isn't afraid to reveal his real name, picture and personal info. On this topic, he answers lots of questions related to VeraCrypt.
The second free and open source alternative I'd recommend is DiskCryptor. It's main drawback is that, unlike TrueCrypt and VeraCrypt, it's only available for Windows. Also, it's developed by anonymous Russians, so there's that.
This is a convincing argument to give VeraCrypt a try. Thanks. +++
Just note that VeraCrypt doesn't support TrueCrypt volumes. If you have stuff encrypted with TC, decrypt it before using VeraCrypt. Here is IDRIX's explanation for the incompatibility:
Quote from: IDRIX
Since 2013, we choose to enhance the key derivation because the TrueCrypt approach doesn't offer the same security as in 2004 when it was released. This explains why TrueCrypt containers can't be supported anymore in VeraCrypt (a conversion tool is planned).
Other than that, VeraCrypt should work just like TrueCrypt.
there are alot of encryption software based on it and it is very very good for a free open source software. i suppose it depends what you want to encrypt really. and how you want to use it truecrypt can be a bit of a pain iv deleted the .file extension a few time by accident XD 
