What is the process like switching from Windows 7 to Windows 10?

There are several factors that you should consider when considering options.  If you have 1 computer and it's for your residence, all of the opinions and input from the other members are valid.  However, if you are requesting this information for your business, I'd recommend finding an IT Partner in your area that can assist you through the transition.  There are many moving parts such as hardware, warranties, application support, user-training, etc that you should consider.  Get an assessment from a qualified Managed Service Provider (MSP) that can guide you through the process to prevent business disruptions, lost data, etc.

I agree with @Jake Mitchell. For business, there is much more to consider than just the upgrade. A big "if" is if your line of business software is compatible with Windows 10 and if the support for that software will continue to support it if you upgrade. 

As far as the actual upgrade process, we always caution against "upgrading" vs a fresh install.  I can't count how many times an upgrade caused the computer to become slower than molasses and unusable. Since the upgrade isn't free anymore you have to purchase a key, might as well do a fresh install. 

Back everything up first of course.

Good Luck!

I love Windows 10 and it doesn't take much to get used to. Depending on the age of your device, you can either upgrade your machine or replace it with a machine with Windows 10 already on it. If the device is more than a couple of years old, I'd just go ahead and replace it with something new. Honestly, that really is the simpler option. If you need help with the transition or have questions/need advice on machines, we're happy to help. 

Windows 10 has matured into a reliable O/S now, and it is not a large learning curve. Like most MS upgrades, they move things around a little and change the look a little, it's still the same old windows interface for the most part. The background changes to security are the biggest reasons to upgrade, but it also does load faster than Windows 7 on the same machine. You can do an in place upgrade to your computer in most cases, or completely reload and start fresh. This is also the time to upgrade your drive to an SSD if you have not already, the combination of SSD with the Windows 10 O/S will give you a significant performance upgrade on any machine. It can make your 4 yr old computer run better than when it was new, and you need to get this done before next year when support for Windows 7 expires. Call if you would like help with this, we are doing several a week these days. 

This is actually a very important question - some of the answer is "it depends".

You need to be sure your hardware can truly accommodate Windows 10. Some vendors have provided a Windows 10 upgrade path such as a Dell system that is not too old will have the licenses ready to move forward to Windows 10, and you can do an in-place upgrade which is not too hard to accomplish.  If you have an older system you may wish to simply upgrade your hardware (i5 processor with a min of 8GB of RAM) to a computer that comes with Windows 10 already installed. Otherwise, you will need to back up your system and perform a full new installation of windows 10.

Short answer trying to not be too technical. 

Simple  just drop in the CD it will ask if you want to update.  Like all updates make sure you have enough disk space it will check  good to take a look and I would suggest a complete defragmentation of the hard drive(s)before you start.  Then of course if you are use any specialized software check with the company that it runs on Win 10.  As for "always leery of changing things that currently work."   People said the same thing about MSSQL update and then they got hi with the SQL attack called MS they said "we fixed that 6 months ago and put out and update didn't you install it? 

It all depends if you are just upgrading a current PC with a Windows 10, or if you are migrating to new hardware.

There are tools that can help you migrate everything even your applications. If you are going with new hardware.

Unfortunately Easy Transfer is not available on Windows 10.

If you are using the same PC you can install Windows 10 and migrate that way with out losing settings, applications and files...

It's fairly straightforward with the media creation tool as has already been suggested.  You can no longer get a free upgrade so you'll be in for a new license.  Between $150 to $200 depending on if you need Home or Pro version.  If you have to pay for the license and the install -- it's likely better to buy a new machine.  If you do keep existing hardware -- I would recommend a clean install as opposed to an upgrade.  Performance will be better with the clean install but you'll need to transfer all your data and programs.

You'll want to get this done by the end of year because support is ending for 7 and you won't be able to get updates any longer.

It depends on the hardware you're running on and if it can handle the Windows 10 OS - drivers can be an issue at times if they do not support it on that hardware. Most of the time it's easier to get a new machine is yours is outdated and migrate the info over. For others who like what they have already, we run the Win10 upgrade assistant and it will check for possible issues/applications that are not supported/etc. and then proceed from their. The license can be purchased from the MS store or online. The in-place upgrade can take a while to complete but it's usually a smooth process. We've moved over 1500 machines year alone as Win7 is coming to an end of support next January.

I suggest using the Windows 10 upgrade checker before doing any OS upgrades.

http://download.microsoft.com/download/C/8/0/C8007C4E-D1DD-4922-A966-3A927E86A033/GWXWebWindows.exe

Here is a link to the Microsoft Community article on checking for windows 10 compatibility.

https://answers.microsoft.com/en-us/windows/forum/windows_other-windows_install/windows-7-81-10-compatibility-testing-for-windows/310e06a4-b181-45ec-ae6d-ee93a1632932