VeraCrypt
Veracrypt is a tool for creating encrypted virtual drives, offering more flexibility than full disc encryption. You can choose the drive's size, name, and location. Unlike full disc encryption, which is noticeable at system boot-up, Veracrypt drives aren't labeled, providing initial obscurity. However, a determined attacker could eventually detect these encrypted files upon mounting.
Hidden Drives
VeraCrypt provides the option for hidden volumes, allowing a "bullshit fake volume" to appear when accessed with one password, while a second hidden volume remains concealed with a different password. This feature can be useful if an attacker demands access; you can provide the fake volume's password, and they would not suspect the existence of a hidden volume. However, it's important to create a convincing setup for the fake volume to avoid raising suspicion from those aware of VeraCrypt's hidden volume feature.
Android Version
VDS Lite is the Android counterpart of Veracrypt, developed by a separate team, offering reduced functionality. It remains helpful for transferring encrypted volumes on mobile devices.
^I don't use this version so don't ask me, it just exist.