.RAR versus .ZIP

[The Eva Monkey]

I have stuff on the server in both .RAR and .ZIP format. And what I want to know from you computer nerds is whether I should use on or the other exclusively? I suspect that I should use one exclusively, for compatibility and consistancy purposes, but I'm not sure which would be better to use.

Anyone care to impart some file compression knowledge?

[badc0de]

Normally the .rar-compression is much better then the .zip-compression. Afaik it's because the algorithm of the .zip-compression has never really been changed, this is good for backwards-compatibily but bad for good compression-ratios. If I don't be at a fault, then an unzip-utility from the computer-stoneage should have no problems unpacking a .zip-file created with the newest version of (Win)Zip (except for long filenames, which it simply truncates).
The algorithm that is used for .rar-achives has changes over the time for better compression-ratios, making .rar-files created with new compression-programs incomplatible with old uncompression-programs, but the newer programs can still open files created with old programs.
So the .rar-fileformat isn't backwards-compatible, but the programs are backwards-compatible (at least the uncompressing part).
I would suggest the .rar-format. I think the argument that most people cannot open .rar-files is out-dated nowadays, because most of the (un)compression-programs handle atleast .zip and .rar.
That's my humble opinion.

[Ornette]

I have stuff on the server in both .RAR and .ZIP format. And what I want to know from you computer nerds is whether I should use on or the other exclusively? I suspect that I should use one exclusively, for compatibility and consistancy purposes, but I'm not sure which would be better to use.

Anyone care to impart some file compression knowledge?

The only things I can think of to consider is: what is being archived and who's going to be looking at it. AFAIK, both types of archives can be unpacked on pretty much any OS. For unices you have "unrar" which I've never run into problems with, although I don't know of a free rar archive creator, since the packing is proprietary, but the unpacking is freely distributed.

RAR archives typically give you better compression, because it'll do multiple passes. The downside is that it'll take longer and be more CPU intensive. ZIP will use multiple methods of compression depending on the files in the archive for the best compression of each file. The downside of this is when the archive contains many small files the gain of multiple methods diminishes and you actually get a larger ZIP.

I don't know much about windows users, but I do know that "unzip" is freely available and even comes with many linux distributions (without having to do an extra install). If you RAR everything instead of ZIP, you may run into instances where someone just wanted to download a collection of images and now has to install WinRAR or something.

Personally, I always use tar/gzip (tar being an archive compression, gzip being similiar to zip minus the archiving) because it's fast and everyone I know can unpack it. The only exceptions are:
1) if I'm making a backup, and there's 80gigs to back up. Using bzip instead of gzip saves me 15 gigs, but it takes an extra 20 minutes to compress. I'm willing to save those 15 gigs because I'm not going to be unpacking this unless I need to restore something. This also goes with really large files that I don't intend to unpack very often.
2) if I'm compressing a relatively large file that I'm posting somewhere for download. If I can save 5 megs using bzip, I'll do it because of the amount of bandwidth I'll be saving (especially if it's going to get downloaded a lot).

[The Eva Monkey]

I should mention that I'm not really interested in the compression side of things. I mainly use it for the purpose of archival, so it's merely for the purpose of getting everything together into one download.

From what I'm hearing, I should output .ZIPs if I want ease of access to downloaders?

[Ornette]

I should mention that I'm not really interested in the compression side of things. I mainly use it for the purpose of archival, so it's merely for the purpose of getting everything together into one download.

From what I'm hearing, I should output .ZIPs if I want ease of access to downloaders?

ZIP also allows you to extract a single file from the archive, instead of uncompressing the entire thing.

Again, I don't know much about windows, it may be that RAR is now included in Vista or whatever new XP release is out now. I know people who still use windows 3.1, but that's their problem.

[Darius]

Well, in my opinion, I would use .rar because if you want to archive things..you can choose if you wan to put in .zip or .rar and that would be beneficial to anyone who doesnt have rar..Also it's pretty quick at archiving...but i wouldnt know which is faster cuz i've on;y used winrar

[badc0de]

ZIP also allows you to extract a single file from the archive, instead of uncompressing the entire thing.

If the .rar-archive isn't a solid archive (all files are handled as one big data-stream), then .rar can also extract single files.

Again, I don't know much about windows, it may be that RAR is now included in Vista or whatever new XP release is out now. I know people who still use windows 3.1, but that's their problem.

Vista: I don't know.
"eXtended Pain": No, not included. Only .zip
Windoof(*) 3.1: Oh, these retro-feelings... where is my C64?
(*) Windoof: A common and intentionally misspelling of Windows (the OS) in Germany, because it sounds almost the same and doof means stupid in German. :twisted:

[drinian]

I would say to use .zip for compatability. It's a lot easier, since the standard is relatively open, to get useful programs to work with zip files. It seems like, with rar, about all you can do is extract or compress.

The difference in file size isn't that great these days either, especially with non-text media files that already have quite a bit of compression anyway.

[The Eva Monkey]

I would say to use .zip for compatability. It's a lot easier, since the standard is relatively open, to get useful programs to work with zip files. It seems like, with rar, about all you can do is extract or compress.

The difference in file size isn't that great these days either, especially with non-text media files that already have quite a bit of compression anyway.

Thanks, that settles it for me. I'll have to convert all my .RARs and put new .ZIPs up on the server.