A mnemonic device or memory device is any learning technique that aids information retention or retrieval in the human memory, often by associating the information with something that is easier to remember.

An acrostic is a poem or other word composition in which the first letter of each new line spells out a word, message or the alphabet. The term comes from the French acrostiche from post-classical Latin acrostichis, from Koine Greek ἀκροστιχίς, from Ancient Greek ἄκρος "highest, topmost" and στίχος "verse". As a form of constrained writing, an acrostic can be used as a mnemonic device to aid memory retrieval. When the last letter of each new line forms a word it is called a telestich; the combination of an acrostic and a telestich in the same composition is called a double acrostic.