What is a File Extension?

This is a recommends products dialog
Top Suggestions
Starting at
View All >
Sign In / Create Account
language Selector,${0} is Selected
Register & Shop at Lenovo Pro
Register at Education Store

Pro Tier Benefits

• Save up to an extra 5% on Think everyday pricing
• Spend SG$10,000, advance to Plus Tier with increased benefits

Plus Tier Benefits

• Save up to an extra 8% on Think everyday pricing
• Spend SG$50,000, advance for free to Elite Tier with increased benefits
• Take advantage of flexible payment options with TruScale Device as a Service.

Elite Tier Benefits

• Save up to an extra 12% on Think everyday pricing
• Take advantage of flexible payment options with
TruScale Device as a Service.
Reseller Benefits
• Access to Lenovo's full product portfolio
• Configure and Purchase at prices better than Lenovo.com
View All Details >
more to reach
PRO Plus
PRO Elite
Congratulations, you have reached Elite Status!
Pro for Business
Delete icon Remove icon Add icon Reload icon
Temporary Unavailable
Cooming Soon!
. Additional units will be charged at the non-eCoupon price. Purchase additional now
We're sorry, the maximum quantity you are able to buy at this amazing eCoupon price is
Sign in or Create an Account to Save Your Cart!
Sign in or Create an Account to Join Rewards
View Cart
Wow, your cart is empty!
Fill it in with great deals
Some items in your cart are no longer available. Please visit cart for more details.
has been deleted
Please review your cart as items have changed.
Contains Add-ons
Proceed to checkout
Popular Searches
What are you looking for today ?
Quick Links
Recent Searches
Hamburger Menu
skip to main content

What is a File Extension?

A file extension is a three or four-letter code that appears at the end of a filename and indicates the type of file it is. For example, .txt stands for text files, .jpg stands for image files and .docx stands for Microsoft Word documents. By knowing what kind of file, it is, your computer will be able to correctly open the file using the correct program.

Why are there different types of File Extensions?

Different file extensions have been designed by software makers to help computers identify which program should be used to open them. This is because certain programs only work with specific file formats, so knowing the filename's extension can help you quickly figure out if you need to install another program in order to open the file.

What happens when I try to open a file without an extension?

When a file does not have an extension, your computer will not know which application should be used to open it. In this case, you may get an error message such as “Windows cannot open this type of file” when you try to double-click on it. You can usually fix this problem by figuring out the correct extension for the file in question and then adding it manually.

Can I change the File Extension?

In most cases yes - but changing the name of your files does not necessarily mean their extensions will also change too. For example, renaming a JPEG image (which has a .jpg extension) will not change its format from JPEG into something else just because you changed its name. But if you simply want to make sure that your files are all named in one specific way with no extra characters or symbols. Renaming them can still be useful in some cases.

Are there any dangers involved when changing File Extensions?

Yes - while most files are safe if you change their names and/or extensions, there are some exceptions like executable (.exe) and batch (.bat) files which can cause damage if they are altered in any way. It is best not to take any chances, especially if you do not know exactly what kind of information these types of files contain or how they could affect your system if opened incorrectly.

What do I do if I download a file with an unrecognized extension?

If you ever come across a strange looking filename ending with some letters or numbers that do not familiarize you first use Google to find out more about them before attempting to open or run them on your computer (the same goes for ones that look like actual words but do not match up with known extensions). If after doing some research things still do not look clear. Just delete it immediately and never attempt to run it on your system.

What is the difference between a file name and File Extension?

The main difference between a file name and its extension is that while the filename identifies what type of file it is, the file extension provides more information such as which program should be used to open it. For example - a .docx file typically represents a Microsoft Word document, but without knowing the extension your computer will not know what program should be used to open it.

How do I change my File Extensions in Windows?

First you need to enable viewing of all file extensions click Start, type folder options into the search box and then click on "Change how Windows Explorer handles file name extensions" under Folder Options. Now you can right-click on any file and select "Rename" to change its extension. Make sure that when changing it you only keep the four letters at the end (do not add anything else). After changing it just hit Enter or click outside of the filename field and you are done.

Are there any benefits to having different kinds of File Extensions?

Yes - by having different types of files with unique extensions, your computer will have an easier time finding which program needs to be used in order to open them correctly. This is especially useful for people who use lots of different applications or work with lots of media files since different programs can handle these differently. It also makes it easier for programs like Microsoft Office or Adobe Photoshop to recognize specific formats when editing or creating documents.

Should I be worried about malicious File Extensions?

Yes - some file extensions are associated with malicious programs and can-do severe damage to your computer if they are opened. To stay safe, it is best to only open files whose filename and/or extension you recognize and that come from reliable sources. To further reduce the risks of getting infected, always keep your antivirus up to date as well.

What is a common example of a malicious File Extension?

The most common type of malicious file extension is .exe. This usually indicates an executable program which could contain a virus or other form of malware. Other malicious file extensions include .bat (batch files), .cmd (command files) and .vbs (Visual Basic script files). It is best not to open any of these types of files unless you know exactly what they are and where they came from.

Is there any way to see what program will open a file by its name or extension?

Yes - if you are trying to figure out what kind of application is associated with a specific file type, one option is to search for its filename or extension on Google. For example - searching for "XLSX" should provide plenty of results that explain what kind of file it is, and which program should be used to open it. Another option is looking at the properties window for the file in question (right-click on the filename then select Properties). Here you should be able to find basic information such as size, date modified, version and type along with the default or preferred programs used for opening it.

What are some of the risks associated with sharing files over the Internet?

Sharing files over the internet can be risky for both you and the person receiving them. For you, this means potentially exposing yourself to viruses, malware, or ransomware if the file you are sharing is from a malicious or untrustworthy source. Additionally, when sending sensitive information online there is always a risk that your data could be intercepted by hackers or accessed by other unauthorized parties.

For those receiving the file, they may face similar risks depending on where they obtained it from and who sent it to them. Additionally, they may face legal repercussions if their country has laws regarding illegal downloading and distribution of copyrighted material. As such, it is important to ensure that the files being shared are safe and legal before sending them to anyone else.

What precautions can I take to protect myself when downloading files?

When downloading files, it is important to be mindful of where they are coming from and what kind of files they are. Be sure that the website or source you are downloading from is trustworthy and not known for spreading malicious software. Additionally, scanning all downloaded files with an up-to-date antivirus program is necessary. This will ensure any threats are detected before they can do any damage. Finally, avoid opening any file types from unknown senders or sources as these could potentially contain malicious content.


Signup for Lenovo email notifications to receive valuable updates on products, sales, events, and more...

Sign up >
coming coming
Starting at
List Price
Est Value
Web Price:
List Price
Est Value (Estimated Value)
List Price is Lenovo’s estimate of product value based on the industry data, including the prices at which first and third-party retailers and etailers have offered or valued the same or comparable products. Third-party reseller data may not be based on actual sales.
Estimated value is Lenovo’s estimate of product value based on industry data, including the prices at which Lenovo and/or third-party retailers and e-tailers have offered or valued the same or comparable products. Third-party data may not be based on actual sales.
Learn More
See More
See Less
View {0} Model
View {0} Models
Shipping options for {0}
Part Number:
See More
See Less
Great choice!
You may compare up to 4 products per product category (laptops, desktops, etc). Please de-select one to add another.
View Your Comparisons
Add To Cart
Add To Cart
We're sorry,
Products are temporarily unavailable.
Continue Shopping
Learn More
Coming Soon
Featured Product
Featured Products
Oops! No results found. Visit the categories above to find your product.
open in new tab
© 2024 Lenovo. All rights reserved.
© {year} Lenovo. All rights reserved.
Compare  ()