File Extension DLL
file extension dll are dynamic-link library files (sometimes also written "dynamic link library" documents) and therefore are an integral part of Microsoft Windows and the applications that runs on it. DLL files are shared between lots of different software programs. Each DLL is a small chunk of applications code comprising tools and instructions to get an application to run a specific hardware device. In the broader sense Microsoft dynamic link-library files sometimes have the expansion .OCX (in the case of files which include ActiveX controls) or even .DRV for older system drivers.
The most common problem people will confront, with regards to DLL files, is not having them. As an instance when you plug a new piece of hardware in your PC and you get an error message saying something such as "DLL file WXYZ.DLL is missing: please install it now." This signifies is that your PC can not find the driver linked to the brand new hardware, because it was not preinstalled with all the operating system and you also haven't subsequently installed it either in the CD, accompanying the product, or downloading it from the manufacturers website.
Like all computer, a file extension DLL can include bug and battle with other software, the consequence being that debatable dynamic-link library documents may undermine the performance of your system by inducing crashes and system slow-downs. In the exact same time some DLLs are updated, for example to include extra functionality, or to accommodate upgraded ActiveX components. This is the reason why it's very important to update drivers and DLLs regularly.
Nevertheless having modern computers share software components creates risks, in addition to opportunities, and all these have come to be known as "DLL Hell." Common DLL problems comprise the incompatibility of a certain DLL with different applications, meaning that an application may use one version of a DLL, however, when installed, another application might overwrite that variant with another (or earlier) version of the same DLL causing problems for the elderly application.
As a final note it is unlikely that you should have to open or edit . DLL files (unless you are a specialist) so in the event that you do get a particular file extension DLL somehow, there is no need to search for a particular application with which to open it (as you would with, say, a .DOC document). Also note that viruses hidden or masquerading as a DLL can infect your PC and thus you should take care when downloading them from the Internet or rescue them in an email.
