|Use any software mentioned here at your own risk.|
Despite the advent of dozens of different compressed/archived file formats since practically the dawn of computing, none seem to have endured quite as well as the zip format (on the PC side, anyway). E-mail attachments and downloaded files are still regularly run through a zip-creating program in order to both decrease the file's size (compression) and to combine multiple files into a single download/attachment (archiving). Microsoft's last few versions of Windows (starting with Millennium, I believe) have included support for zip files in the Windows Explorer (allowing you to extract files from a zip file without using special software), but if you want to create zip files, or do more complex tasks with them, you need another tool to help you. One of the most common programs to work with zip (and other archive/compression format) files is WinZip, a $30 program that lets you create zip files, adjust the compression settings, create zip files that span multiple disks, rename files within a zip archive, add files to a zip archive, and more. But why pay $30 for WinZip when you can download ZipCentral for free?
ZipCentral is a tool for creating, extracting from, and otherwise working with zip files. To extract the files from a zip archive, you can either double-click on the archive to open it in ZipCentral (like the example screen shown here), highlight the files you want to extract, and click the large Extract button at the top of the screen. You're then asked where you'd like to extract the files to, and given some other options for what to do with the files (extract folders, overwrite existing files, etc.). You can also right-click on a zip file in the Windows Explorer and select "Extract Here" to take all the files out of a zip archive and place them in the same folder as the zip archive itself, or "Extract To...", which brings up a screen to let you choose the folder to extract the files into. To create an archive, you can highlight files in Windows Explorer, right-click and choose "Add to zip", run ZipCentral and click the "New" button, or run ZipCentral and drag files from the Explorer onto the ZipCentral screen. You're first asked to name the zip archive, then given some options for how to add the files to the archive (include folder name/path, compression level, etc.). Once the files are listed in the ZipCentral screen, the archive is complete and you can exit ZipCentral or add more files. You can even rename the files within the archive by right-clicking on a file in the ZipCentral screen and choosing "Rename", or remove a file from an archive by right-clicking and choosing "Delete".
ZipCentral also lets you create self-extracting and disk-spanning archives, which make distributing zip files easier. A self-extracting archive is a zip file that's been turned into an executable file (i.e. it ends with .exe). Anybody can extract the archived files without having any zip software at all. This way, you don't have to worry about whether the person you need to send some files to has zip-extracting software or not - the file you send doesn't need any special software to be used. The two downsides to self-extracting archives are that the resulting archive files are a bit larger (about 40K, because ZipCentral has to add a program to the file to do the unzipping) and many e-mail systems block executable files (either don't allow them to be sent/received, or don't allow them to be saved to the computer), so sometimes it isn't helpful to create a self-extracting archive after all. But in general, and especially for an archive to be downloaded off the Internet, I think it makes sense to use self-extracting archives instead of regular zip files. A disk-spanning zip is a large zip file that's been broken up into smaller pieces so that they fit on some specific media. This was more useful with floppy disks were common, because you could take a 10MB file and create 8 1.4MB zip files out of it (each big enough to fit on a single floppy disk). Unzipping programs would be able to tell that the zip file was made of multiple pieces and the process of unzipping/extracting would automatically instruct the user to insert the next disk. While we don't often use floppy disks to transfer information anymore, disk spanning is still helpful for other types of media, like CD-ROM, where you're still limited in the amount of data a single disc can hold. Say you've got 3GB of data (either a single file or many files) that you want to put onto CD so you can store it or give to someone else. When you create a new zip file in ZipCentral, check the box that says "Use disk spanning" then click on the "Options" button and specify how many bytes to make each partial zip file (650MB, the size of a standard CD-ROM, would be entered as 650000000 for 650 million bytes). ZipCentral will then create 3 zip files, each no larger than 650MB so that they easily fit on a CD-ROM, and whoever you give the discs to can extract all the files as if it was one large zip file. The final feature I'll mention, though ZipCentral has others, is that you can assign a password when you add files to an archive, so that the files can't be removed from the archive unless the person doing the extracting knows the password. Different files in the same archive can even have different passwords, and some can have no password at all. Without knowing the password, someone can only extract the files that don't have passwords. Be forewarned, however, that the password encryption used by the zip format standard isn't all that strong, and there are programs out there that can pretty easily get at data in a zip file that's been password protected. If you really want your information to be safe, encrypt your data first using a strong encryption tool and then zip the encrypted file.
ZipCentral is pretty easy to use and has a nice, professional interface and help. It doesn't have as many automated features as WinZip (for example, right-clicking on a .zip file to turn it into a .exe, or being able to use copy-paste to add files to or extract them from an archive), but that shouldn't matter unless you're using a zip tool for several hours a day. ZipCentral has been mostly stable on my system (Windows 98), but it has occasionally crashed (one time using up 100% of my CPU so that I had to reboot) with a system error (which, interestingly enough, did not cause ZipCentral to quit, and I was able to keep using it). But I'm willing to forgive a few faults in free software (in fact, I've come to expect it), and overall ZipCentral does an excellent job of letting me do what I need to do with zip archives. If you need to create zip archives or do anything more complicated than extract files from one, consider giving ZipCentral a try.
|©2019 Tyler Chambers|