In order to protect your data from any kind of malicious activity it is advisable to use the most effective document manager which allows you to store your documents in an organized manner and also provides security to your data.
These document managers make use high password strength requisites, allow resets, limited number of logins etc.
They also are equipped with Granular Authorization which have permission levels thus ensuring you of the fact that individuals are provided with only that information that is necessary for them to know and nothing more.
These systems have an option of protecting your presentations and documents with passwords.
Document manager systems also employ Secure Sockets Layer (SSL) / Transport Layer Security (TLS) on your data which is transmitted between the server and your computers.
With these systems, both your in-flight and at-rest data is encrypted thus giving you the right kind of security for all forms of data.