If there was a kind of rating of types (extensions) of files that exist on users' computers or servers on the Internet, then, without a doubt, the TOP-10 of this list would include Microsoft Excel files - spreadsheets. This is due to many reasons:
- the widespread use of tables for calculations in business and e-commerce;
- distribution of the Microsoft Office suite on hundreds of millions of computers around the world;
- the convenience of processing, storage and systematization of large volumes of data and calculations;
- Macro programming language built into the software shell;
- OLE support;
- a single format for storing data in xlsx and xls formats.
How to open a spreadsheet file from Microsoft? To open the xls file, you need to use certain programs, the choice of which will depend on the goals pursued.
There are three ways to open an XLS file for editing (making changes to it):
Use Microsoft Office Excel. It is a wrapper for creating and modifying spreadsheets. This requires the purchase of an office suite from Microsoft, which not everyone can afford.
There are several free software packages that support the xls format. How to open files of this kind? The user is available for free download and use 2 of these packages: Libre Office OpenOffice.
You can open the file through a web interface that supports xls. How to open such tables on the Internet? Of course, through GoogleDocs. If you have an email account from Google, then there will be no problems with how to open the xls file. Along with access to the mailbox, the user gets the opportunity to download, open and edit spreadsheet files online. Note: Recently, Google Docs have stopped saving files in the obsolete XLS format. If you want to save the file in the old version in order to use it later, it is recommended to save its duplicate for editing and changes in the container file - XLSX. It is an archive of xml files that describe the structure of the spreadsheet and the data in it.
If you only need to view the contents of the spreadsheet file, you can use the free utility available for download on the Microsoft website. A small program that, after installation, takes about 180 MB of disk space, is called Excel Viewer. It is intended only for viewing and printing xls files. How to open and download bulky software packages and spreadsheet editors? It is better to use a relatively small, free utility from the founder of this format. Modern versions of the program support not only xls, but also xlsx.
Safety and security
How? Can't open an xls file? A password is required, but is it unknown? Such cases are not uncommon. It happens that a user, having created a spreadsheet with confidential information, protects it with a password and ... "safely" forgets it.
In such cases, you can use one of the many free password cracking programs for xls files. The fact is that in versions of Excel until 2003, 16-bit key encryption was used with the default security settings. For modern brute force programs, it’s a matter of minutes to sort through so many passwords.
The author does not specifically cite the names of the programs for selecting passwords, because there are many who want to use them for personal or illegal purposes. Honest users would like to recommend keeping important and confidential tables in xlsx format. This is the format for new versions of Excel. The key (password) there is already encrypted with 128 bits, which are hashed several thousand times by the SHA1 cryptographic algorithm. It will take years to crack such a password. At the same time, having received strong protection, it is necessary to remember “your” passwords, since it will be impossible to recover them.