Any direct or indirect action on a damaged or undamaged manuscript or collection of manuscripts, for increasing their life is conservation. This can be Preventive or Curative.

Preventive conservation seeks to reduce the future risk of deterioration. It includes measures such as controlling the temperature and humidity of the storage area of manuscripts and regular inspection of the condition of the manuscript/collection.

Curative conservation is any direct action on the manuscript(s) to prevent active deterioration. For instance, fumigation of manuscript(s) infested with insects.

Manuscripts are sometimes subjected to restoration. This is different from conservation as the former aims at make the manuscript(s) look as close as possible to their original form. This is mainly to enhance their visual appeal. This may involve steps like repainting illustrations and removing pencil marks from a folio.