I can be quite forgetful on a regular basis ! I suppose age has something to do with that :)
Forgetting or disremembering is the apparent loss or modification of information already encoded 
My brain must not encode right then.  I do have tricks to remember things though.
It reacts  with  a spontaneous or gradual process in which old memories are unable to be recalled from memory storage.
 Forgetting also helps to reconcile the storage of new information with old knowledge.
remembering, learning and retaining new information are a few of the most common complaints of older adults.
 Retention improves with increased rehearsal. This improvement occurs because rehearsal helps to transfer information into long-term memory – practice makes perfect.
Memory rehearsal
Memory rehearsal is a term for the role of repetition in the retention of memories. It involves repeating information over and over in order to get the information processed and stored as a memory.
Types.
Types Maintenance rehearsal.
Maintenance rehearsal is a type of memory rehearsal that is useful in maintaining information in short term memory or working memory. Because this usually involves repeating information without thinking about its meaning or connecting it to other information, the information is not usually transferred to long term memory. An example
Forgetting
Forgetting or disremembering is the apparent loss or modification of information already encoded and stored in an individual's long-term memory. It is a spontaneous or gradual process in which old memories are unable to be recalled from memory storage. Forgetting also helps to reconcile the storage of new information with old knowledge. Problems with remembering, learning and retaining new information are a few of the most common complaints of older adults. Memory performance is usually related to the active functioning of three stages. These three stages are encoding,