From the year 1944, the Brazilian National Library adopted the microfilming process as an important way of documentary preservation due to its characteristics of durability, longevity and allegiance to the original contents. The microfilm is a steady support, it has definite techniques and standards and the greatest characteristic that defines it, as means of preservation is its life expectancy, which can reach to 500 years.
The microfilming in BN was initiated with titles edited in the 21st century, many collections highly consulted, incomplete, spoiled and existing only in private heritage. In 1978 the National Plan of Brazilian Periodicals Microfilming was created with the general purpose of locating, recovering and preserving the serial collections of Brazil.