Snails can have a long life. The life span for snails depends on their habitat and the species. Some of them only live for about 5 years. However, others in the wild are believed to be up to 25 years old in unusual occasions. 3.
Facultative means optional or discretionary (antonym obligate), used mainly in biology in phrases such as: 1  Facultative anaerobe, an organism that can use oxygen but also has anaerobic methods of energy production. It can survive in either environment. Facultative biped, an animal that is capable of walking or running on two legs as well as walking or running on four limbs or more, as appropriate.
Information retrieval (IR) is the activity of obtaining information resources relevant to an information need from a collection of information resources. Searches can be based on full-text or other content-based indexing. Information retrieval is the science of searching for information in a document, searching for document themselves, searching for metadata that describe data and for databases such as text, image or sound. Automated information retrieval systems are used to reduce what has been called information overload.