Hvad bruges .CER og .VCF filer til

Herunder 2 bud på, hvad det kan være for filer, fundet på:

http://www.file-extensions.org/

File extension CER description:
Fortran is a general-purpose, procedural, imperative programming language that is especially suited to numeric computation and scientific computing. Originally developed by IBM in the 1950s for scientific and engineering applications, Fortran came to dominate this area of programming early on and has been in continual use for over half a century in computationally intensive areas such as numerical weather prediction, finite element analysis, computational fluid dynamics (CFD), computational physics, and computational chemistry. It is one of the most popular languages in the area of High-performance computing and programs to benchmark and rank the world's fastest supercomputers are written in Fortran.

Fortran (a blend word derived from The IBM Mathematical Formula Translating System) encompasses a lineage of versions, each of which evolved to add extensions to the language while usually retaining compatibility with previous versions. Successive versions have added support for processing of character-based data (FORTRAN 77), array programming, module-based programming and object-based programming (Fortran 90 / 95), and object-oriented and generic programming (Fortran 2003).

vcf file icon.vcf    vCard file
vcf file icon.vcf    Vevi configuration file
vcf file icon.vcf    WorldToolKit objects
vcf file icon.vcf    VirtualDub processing settings
vcf file icon.vcf    Skype contacts file
/ptj_11

Ved det er en vCard fil og et tilhørende .cer fil.

Men hvad bruges de til

Vcard filen indeholder dine kontaktoplysninger, cer filen er sansynligvis din certificat oplysninger.
/ptj_11

Dårlig forklaring i den sidste.
Dine kontaktoplysninger for at modtageren kan komme i kontakt med dig, og cer filen skal vel bruges som godkendelses fil.
/ptj_11

Fandt aldrig ud af hvordan de skulle bruges og til hvad