7-Zip

7zip (also known as 7-Zip) is a compression utility built to allow you to compress files on your hard drive into one easy to manage archive. This then becomes much easier to distribute and back-up. For example, you could move it onto a portable drive where you could keep it just in case, or you could give it to other people just by sending them the one file. It also reduces the size by getting rid of the excess space.

7zip also allows you to extract these archives. If you've been downloading data from the internet you'll probably have come across some of the more popular formats before such as ZIP and RAR. This program allows you to take one of these and then get the original files back out of it so you can work with them. You're more likely to need this feature than the ability to create your own compressed archives we've found.

The utility uses complex algorithms to make the archives as small as it can do, which is why it is still used commonly today even after over 10 years of being available to users.

Required Operating System

Windows 2000/XP/2003/Vista/7

Application Type

File Size

1.1MB

Date Created

July 18th, 1999

Software Version

9.2.2

Last Updated

April 18th, 2011

Required

Windows OS, hard disk space

Download Link

7zip Download

Our Review

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To most people, the term "CPU threading" probably sounds rather confusing, something that you have no idea what it means or how it relates to this software. What we can tell you is that it's very important and can be used to your advantage if you're on a relatively powerful computer. What it can do is speed up the time it takes to both extract an archive as well as compressing files into one, you just have to configure the settings correctly.

Ordinarily in this program and in others, one core of your processor is used for the job. This is fine in most cases but if you're working with a large file it can take a lot of time, so if you're lucky enough to be on a powerful machine which is, for example, on a quad core processor then utilizing these four cores would be a really good thing to do.

Enabling this is very easy to do, too. All you need to do is go into the Preferences panel of the application and then select the threading options. Set the number of cores you want to use and then you're ready to go, but remember that doing this will increase the amount of CPU you're using at the time.

This feature is mainly for those who know what they're doing when it comes to technology and computers, the average user will probably never need to use this or even know why it would be used. For those who are interested, though, we'll give a bit of an explanation so that you have better knowledge about how the whole thing works.

The command line is something you may have seen before - basically a black screen with white text on it, where you can enter commands which the operating system will then execute for you. You can make programs which use the command line to do certain tasks, for example you could do some calculations or write to a file. With this feature, you'll be able to extract and compress files with it too.

There's a separate EXE file included in the package which you can then call on the command line whenever you need to use 7-Zip. Note that this is not the main EXE that you run whenever you want the graphical interface so do be careful when you're trying to call it. You'll find it in the same directory but under the file name "7za.exe".

One of the unfortunate things that can happen when you're storing and transferring data is corruption. It's something that a lot of people won't have experienced yet but will at some point and it could cause huge problems. Basically, this is where some of the data becomes malformed, making it seem abnormal and ruining the entire file usually. You can see that back-ups are definitely something you should be taking if you want your data to be secure. What happens when one of your archives becomes corrupt?

In ordinary circumstances, you'd have no other choice but to re-create the archive if you had the ability to or download it from wherever you got it from. This may not be possible, which could lead to the loss of your data completely as you become unable to open it. You should be happy though because this utility actually does its best to repair corrupt files. If only the file names have been damaged and not the actual data inside of them (quite possible) then it can work around this by simply renaming the names and making it into a valid archive once again, ready for you to use. This won't work in all cases but is definitely worth a try.

Keeping you and your data safe should be something that you really take an interest in. You could have private and sensitive information on your computer that you don't want the general public or hackers to get into, which is why you need to keep it to yourself where nobody else will be able to get into it. The utility offers some more advanced methods of protection but in this small section we'll just discuss the basics.

The first thing which you can do is keep your archives deep into your hard drive. This is more likely to keep anyone who has access to it from finding it except yourself. Files on the "Desktop" or in "My Documents" are likely to be looked at first by an intruder. This method alone does not keep you safe though. You should also be careful about what you name your archive so that it isn't too obvious.

Keeping your archives stored on an external piece of media such as a USB stick is another good way of keeping yourself safe. Anything important can then go onto it as long as it isn't always plugged into your machine. That way, if you were hacked the attacker wouldn't be able to get the data on the pen drive.

This is something that comes specifically in the software package we're discussing on this page. We've talked a bit about the basics of keeping your compressed files safe but that isn't really enough in the real world. You need something more concrete which will help you along the way, and one of these things is file encryption. Not only do you compress your files but you also encrypt the archive itself so that nobody except you can access it.

There's a few ways of doing this actually, 7-Zip actually provides 256-bit encryption which you can enable which makes it very difficult to extract. Of course you could be caught up in this yourself and then struggle to get your own files back but this is up to you really. This is of course one of the more advanced ways.

Another very simple way of doing would simply rename the archive from a ".7z" or ".zip" file to something like a ".txt" file. You won't be able to open it, any hackers will think it is just a text file - whenever you need it you can rename it yourself. Not a sure-fire way but it's worth a try if the data is important.

We think that this is the best way of keeping your data secure providing you don't forget the security details yourself. If you make it so that the extract cannot be extracted without providing a password you save yourself a lot of hassle because even if somebody else obtains the archive, they still won't be able to look inside of it. There's a few different ways of doing this depending on the type of encryption and safety that you're wanting.

ZIP files are probably the most common type of archive, but when you password protect one of these anyone can still see all of the file names in the archive, they just aren't able to extract them. Depending on the type of data and the names themselves this may or may not be a problem for you, but luckily .7z files don't have the same problem.s

If you create a .7z file and password protect it, nobody will be able to see anything about the archive without the password, helping to keep it very secure. To do this in the first place, all you need to do is specify the key phrase when it asks for it when you're creating the archive for the first time.

This is the first type of file that we're going to talk about that is supported by this application. We're doing this because of how popular it is, it really is the industry standard format for archives and is supported by default by the majority of operating systems released. The problem is that a lot of these defaults don't do the job well - for example, you can extract directory from Windows Explorer if you wanted to but the graphical interface isn't as good and there definitely isn't as many features included.

To stick with the industry, this does a fairly similar thing to the rest of the tools but it tries to make it quicker by optimizing the utility as well as giving you neat options such as to use multiple cores on a processor. There are a lot of reasons for choosing to use this particular format, though.

Perhaps the biggest one of the all is compatibility. If you're needing to share it with other people then this is the one you're going to go with because you know that everyone can open it. On the other hand, with the other formats you're not likely to get the same thing, they won't be able to open it up straight away.

Most people don't actually know this but the 7zip software can actually use its own format too, called a .7z file. They used to be much more popular back in the day but you can still see them used now, and obviously you can still create them if you want to do so. This is a format specifically built for this application, there may be others that can support this now but it was originally developed for this one.

There are reasons why you may want to consider using this too. In a lot of cases, the compression it achieves is significantly than what you would get in a ZIP file, which means only one thing - smaller file sizes, which is exactly what you want. By having a format native to this utility, it also means extra privacy and features can be added without worrying about how other tools will deal with it.

Compatibility is something that you have to be really careful of though. If you're going to use this we recommend that you stick to producing personal archives with it that aren't destined for other people, else you may find them with the problem of not being able to use the data that you've just sent them.

We've gone into detail about two of the main archive formats that are supported by this program but there are tons more included that you may not be aware of either. We're going to briefly talk about a few of them now so that you have more information.

RAR - This is a format that is used by another utility of a similar nature but has become a standard in recent years. It provides good compression rates whilst keeping an average compatibility rate too, so an overall good compromise for users.

ISO - This is normally associated with disk images and software but you can find them simply being used as archives too and with this tool you'll be able to extract them as well as create them, although may struggle to do the same on other systems so you need this to be installed on them all.

GZIP - Often used on Mac OS X and Linux, this is something else that can be useful when packing data because it can offer the highest compression rates in the industry, so it is definitely worth looking into.