I use the following .gitignore for C# projects. Additional patterns are added as and when they are needed.

[Oo]bj
[Bb]in
*.user
*.suo
*.[Cc]ache
*.bak
*.ncb
*.log 
*.DS_Store
[Tt]humbs.db 
_ReSharper.*
*.resharper
Ankh.NoLoad

I understand this is an old question, still sharing an information. In Visual Studio 2017, you can just right click on the solution file and select Add solution to source control

This will add two files to your source folder.

1. .gitattributes
2. .gitignore

This is the easiest way.

Using Visual Studio to add a .gitignore

Open Visual Studio and the solution needing an ignore file. From the top menu select Git > Settings.

The above will open Visual Studio’s Options with Source Control > Git Global Settings selected. From the list on the left select Git Repository Settings and then click the Add button for Ignore file.

The above will add (and stage for committing) a .gitignore file with all the proper files ignored for a typical Visual Studio setup.

https://elanderson.net/2020/10/add-git-ignore-to-an-existing-visual-studio-solution-new-git-experience/

Note that if you already have a .gitignore file in your repo root, the "Add" button will instead say "Edit" and pressing that button will simply open the file without updating it, which isn't very helpful. In this case you could first rename your .gitignore file, click the Add button, unstage the new .gitignore file, and then merge in your saved copy changes however you'd like.

On Visual Studio 2015 Update 3, and with Git extension updated as of today (2016-10-24), the .gitignore generated by Visual Studio is:

## Ignore Visual Studio temporary files, build results, and
## files generated by popular Visual Studio add-ons.

# User-specific files
*.suo
*.user
*.userosscache
*.sln.docstates

# User-specific files (MonoDevelop/Xamarin Studio)
*.userprefs

# Build results
[Dd]ebug/
[Dd]ebugPublic/
[Rr]elease/
[Rr]eleases/
[Xx]64/
[Xx]86/
[Bb]uild/
bld/
[Bb]in/
[Oo]bj/

# Visual Studio 2015 cache/options directory
.vs/
# Uncomment if you have tasks that create the project's static files in wwwroot
#wwwroot/

# MSTest test Results
[Tt]est[Rr]esult*/
[Bb]uild[Ll]og.*

# NUNIT
*.VisualState.xml
TestResult.xml

# Build Results of an ATL Project
[Dd]ebugPS/
[Rr]eleasePS/
dlldata.c

# DNX
project.lock.json
artifacts/

*_i.c
*_p.c
*_i.h
*.ilk
*.meta
*.obj
*.pch
*.pdb
*.pgc
*.pgd
*.rsp
*.sbr
*.tlb
*.tli
*.tlh
*.tmp
*.tmp_proj
*.log
*.vspscc
*.vssscc
.builds
*.pidb
*.svclog
*.scc

# Chutzpah Test files
_Chutzpah*

# Visual C++ cache files
ipch/
*.aps
*.ncb
*.opendb
*.opensdf
*.sdf
*.cachefile
*.VC.db

# Visual Studio profiler
*.psess
*.vsp
*.vspx
*.sap

# TFS 2012 Local Workspace
$tf/

# Guidance Automation Toolkit
*.gpState

# ReSharper is a .NET coding add-in
_ReSharper*/
*.[Rr]e[Ss]harper
*.DotSettings.user

# JustCode is a .NET coding add-in
.JustCode

# TeamCity is a build add-in
_TeamCity*

# DotCover is a Code Coverage Tool
*.dotCover

# NCrunch
_NCrunch_*
.*crunch*.local.xml
nCrunchTemp_*

# MightyMoose
*.mm.*
AutoTest.Net/

# Web workbench (sass)
.sass-cache/

# Installshield output folder
[Ee]xpress/

# DocProject is a documentation generator add-in
DocProject/buildhelp/
DocProject/Help/*.HxT
DocProject/Help/*.HxC
DocProject/Help/*.hhc
DocProject/Help/*.hhk
DocProject/Help/*.hhp
DocProject/Help/Html2
DocProject/Help/html

# Click-Once directory
publish/

# Publish Web Output
*.[Pp]ublish.xml
*.azurePubxml

# TODO: Un-comment the next line if you do not want to checkin 
# your web deploy settings because they may include unencrypted
# passwords
#*.pubxml
*.publishproj

# NuGet Packages
*.nupkg
# The packages folder can be ignored because of Package Restore
**/packages/*
# except build/, which is used as an MSBuild target.
!**/packages/build/
# Uncomment if necessary however generally it will be regenerated when needed
#!**/packages/repositories.config
# NuGet v3's project.json files produces more ignoreable files
*.nuget.props
*.nuget.targets

# Microsoft Azure Build Output
csx/
*.build.csdef

# Microsoft Azure Emulator
ecf/
rcf/

# Microsoft Azure ApplicationInsights config file
ApplicationInsights.config

# Windows Store app package directory
AppPackages/
BundleArtifacts/

# Visual Studio cache files
# files ending in .cache can be ignored
*.[Cc]ache
# but keep track of directories ending in .cache
!*.[Cc]ache/

# Others
ClientBin/
[Ss]tyle[Cc]op.*
~$*
*~
*.dbmdl
*.dbproj.schemaview
*.pfx
*.publishsettings
node_modules/
orleans.codegen.cs

# RIA/Silverlight projects
Generated_Code/

# Backup & report files from converting an old project file
# to a newer Visual Studio version. Backup files are not needed,
# because we have git ;-)
_UpgradeReport_Files/
Backup*/
UpgradeLog*.XML
UpgradeLog*.htm

# SQL Server files
*.mdf
*.ldf

# Business Intelligence projects
*.rdl.data
*.bim.layout
*.bim_*.settings

# Microsoft Fakes
FakesAssemblies/

# GhostDoc plugin setting file
*.GhostDoc.xml

# Node.js Tools for Visual Studio
.ntvs_analysis.dat

# Visual Studio 6 build log
*.plg

# Visual Studio 6 workspace options file
*.opt

# Visual Studio LightSwitch build output
**/*.HTMLClient/GeneratedArtifacts
**/*.DesktopClient/GeneratedArtifacts
**/*.DesktopClient/ModelManifest.xml
**/*.Server/GeneratedArtifacts
**/*.Server/ModelManifest.xml
_Pvt_Extensions

# LightSwitch generated files
GeneratedArtifacts/
ModelManifest.xml

# Paket dependency manager
.paket/paket.exe

# FAKE - F# Make
.fake/

In Visual Studio 2015 Team Explorer > Local Git Repositories > Project > Settings > Git > Repository Settings > Ignore & Attribute Files.You can add .gitignore file with items should be ignored in visual studio solutions by default.

Here's an extract from a .gitignore on a recent project I was working on. I've extracted the ones that I believe are related to Visual Studio, including the compilation outputs; it's a cross platform project, so there are various other ignore rules for files produced by other build systems, and I can't guarantee that I separated them out exactly.

*.dll
*.exe
*.exp
*.ilk
*.lib
*.ncb
*.log
*.pdb
*.vcproj.*.user
[Dd]ebug
[Rr]elease

Perhaps this question should be Community Wiki, so we can all edit together one master list with comments about which files should be ignored for which types of project?

Credit to Jens Lehmann for this one - if you keep source directories separate to your compiler project files and build output, you could simplify your .gitignore by negating it:

path/to/build/directory/*
!*.sln
!*.vcproj

You don't say what language(s) you're using, but the above should work for C++ projects.

You can create or edit your .gitignore file for your repo by going to the Settings view in Team Explorer, then selecting Repository Settings. Select Edit for your .gitignore.

It automatically creates filters that will ignore all the VS specific build directories etc.

More info have a look here.

It should depend on the project or language you are using. So extensions related to build, vs folder , sln file , bin folder etc are to be included. For full list of git ignore files you can check this repo gitignore for visual studio

Some project might want to add *.manifest to their visual studio gitignore.io file.

That is because some Visual Studio project properties of new projects are set to generate a manifest file.

See "Manifest Generation in Visual Studio"

But if you have generated them and they are static (not changing over time), then it is a good idea to remove them from the .gitignore file.

That is what a project like Git for Windows just did (for Git 2.24, Q4 2019)

See commit aac6ff7 (05 Sep 2019) by Johannes Schindelin (dscho).
^{(Merged by Junio C Hamano -- gitster -- in commit 59438be, 30 Sep 2019)}

.gitignore: stop ignoring .manifest files

On Windows, it is possible to embed additional metadata into an executable by linking in a "manifest", i.e. an XML document that describes capabilities and requirements (such as minimum or maximum Windows version).
These XML documents are expected to be stored in .manifest files.

At least some Visual Studio versions auto-generate .manifest files when none is specified explicitly, therefore we used to ask Git to ignore them.

However, we do have a beautiful .manifest file now: compat/win32/git.manifest, so neither does Visual Studio auto-generate a manifest for us, nor do we want Git to ignore the .manifest files anymore.