Attribute based encryption (ABE) is a generalization of public encryption schemes that gives a way to target the group of people who are authorized to decrypt.

In key-policy ABE, an access policy is encoded into the user’s secret key and ciphertexts are associated with a set of attributes.

In ciphertext-policy ABE, the secret key is associated with a set of attributes and the access policy is encoded in the ciphertext at the encryption time.

Searchable Symmetric Encryption is a cryptographic protocol designed to securely make search queries on an untrusted cloud server. Hence, databases can securely be outsourced without compromising their usability.
After a search request, the cloud server can answer the list of the all the entries matching the requested keyword without knowing neither the keyword nor the entries as everything is encrypted.

Secure Multi-party Computation is a set of techniques allowing several entities to jointly compute results on their inputs without revealing their individual data to others.
This tool is particularly useful when the different entities must remain cautious about the other participants even if they want to cooperate on a computation.

Functional Encryption is a cryptographic technique that enables entities to execute specific operations on encrypted data – and output the result in clear, but it will never reveal the inputs of the computation nor the intermediate values.
Performing computations on the data and obtaining the results of these computations is allowed only to authorized entities by data owner who will generate specific keys associated to specific computations.

Fully Homomorphic Encryption is a form of encryption that allows to perform operations on ciphertexts without having access to the underlying source data or manipulating any secret key.
Results of these computations are also encrypted and only data provider having the secret key is able to decrypt them. This technique does not require any trusted authority to distribute the keys, the entities act independently, not assuming any trusted party.