When comparing C# vs Pascal, the Slant community recommends Pascal for most people. In the question“What is the best programming language to learn first?” Pascal is ranked 5th while C# is ranked 7th. The most important reason people chose Pascal is:
Because of the verbosity and easy syntax, Pascal language is relatively easier to be learned and understood, even for someone who has no programming knowledge. It's said that Pascal code —if written well— is like reading pseudo code.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro .NET is a great toolbox
C# runs on top of the .NET framework, which provides many libraries containing classes used for common tasks such as connecting to the Internet, displaying a window or editing files. Unlike many other languages, you don't have to pick between a handful of libraries for every small task you want to do.

Pro Incredibly Well-Engineered Language
Where other languages invoke the feeling of being a product of organic growth over time, C# just feels like an incredibly well-designed language where everything has its purpose and almost nothing is non-essential.
Pro Awesome IDE for Windows
On Windows, Visual Studio is the recommended C# IDE. It provides a very flexible GUI that you can rearrange the way you want and many useful features such as refactorings (rename a variable, extract some code into a method, ...) and code formatting (you can pick exactly how you want the code to be formatted).
Visual Studio also highlights your errors when you compile, making your debug sessions more efficient since you don't have to run the code to see the mistakes. There's also a powerful debugger that allows you to execute the code step-by-step and even change what part of the code will be executed next. In addition to giving you all the line-by-line information you'll need in a hassle-free manner, Visual Studio has stuff you can click on in the errors window that will take you to the documentation for that error, saving you several minutes of web searching.
In addition to all of this, Visual Studio has an intuitive, intelligent, and helpful graphical user interface designer that generates code for you (the best of WYSIWYG, in my opinion), which is helpful for new programmers. Being able to create a fantastic-looking UI with one's mouse and then optionally tweak with code helps make programming fun for beginner developers.
Visual Studio also has the best code completion --Intellisense is every bit as intelligent as the name says it is. It, as well as VS's parameter hinting, is context-, type-, user-, and position-sensitive, and displays relevant completions in a perfectly convenient yet understandable order. This feature allows a new programmer to answer the questions "What does this do?" and "How do I use it?" right then and there rather than having to switch to a browser to read through extensive documentation. This allows the programmer to satisfy their curiosity before it is snuffed out by several minutes of struggling through exhaustive documentation.
And for the more adventurous and text-ready developer, Microsoft does the best job of ensuring that everything, from interfaces and wildcard types down to Console.WriteLine("") and the + operator, is well-documented and easy to understand, with relevant and well-explained usage examples that manage to be bite-size yet complete, simple yet truly helpful. The reference site is easy to navigate, well-organized, clean and uncluttered, up-to-date, and fresh and enjoyable to look at, and every page is well-written with consideration for readers who are not C# experts yet want to read about changing the console background color.
The best part? It's free! Visual C# Express contains all of the features described above, at zero cost. If you are a student, you can probably get Visual Studio Professional from your university, which also includes tools for unit testing and supports plugins.

Pro Supports some functional features
C# is primarily object-oriented, but it also supports some features typically found in functional languages such as lambdas, delegates and anonymous classes. Methods can be treated like any other object, and the Linq query system operates on monads with lazy evaluation (though it hides this with a lot of syntactic sugar).
You don't need to use these features to code in C#, though, so you can start with OOP and then learn about them.
Pro Great introduction to object-oriented programming
Object-oriented programming is the most widely-used paradigm. C# offers support for common OOP features such as classes, methods and fields, plus some features not found in competing languages like properties, events and static classes.
C# code is much more readable thanks to the syntactic sugar it offers. You can truly concentrate on your code, not on the way it's implemented.
Pro Best language for Windows programs
C# is clearly the best choice for Windows programs. The .NET framework contains everything you need to build great-looking apps, without having to learn the confusing Win32 API or download a ton of external libraries. C# can also be used to build Windows 8's "modern" apps.
Pro Very high demand in the industry
C#'s been around for just the right amount of time, is regularly updated with useful additions, is versatile, easy to write & read, & has excellent tooling support. This means it is a top choice for many organizations & will remain so for the foreseeable future.
Pro Can mix high and low level programming
You can code at the high level without worrying about pointers and memory management, but if you so choose you can switch to lower level programming with direct memory management and pointer manipulation (though you need to compile to specifically allow this).
Pro Awesome IDE for cross-platform development
Visual studio has embraced cross platform development over the past 3 years. With Visual Studio Code, you now have a light, and quick IDE variant available for free as well.
Pro With ASP CORE a good language to learn
With CORE you are no longer just limited to Windows, so a language worth learning.
Pro Supported on many platforms
C# can be used for Windows apps, Linux apps, OS X apps, Windows 8 "modern" apps, websites, games, iPhone apps, Android apps, Windows Phone apps, and more.
If you want to create a cross-platform application, you can share most of the code and write one GUI for each platform.
Pro .NET truly universal
With .NET core it is a truly universal programming language which support desktop apps (Windows), Mobile apps (Xamarin), Web Apps (ASP.Core MVC). Also is perfectly fit to serverless programming for micro services. Soon it will be also support Web assembly (Blazor).
Pro Great language for Unity game engine
Unity provides a selection of programming languages depending on preference or knowledge - C#, JS, Boo and UnityScript. C# is arguably the most powerful with better syntax and stronger language structure. It allows using script files without attaching them to any game object (classes, methods inside unattached scripts that can be used at any time). There are more tutorials and information for C# than UnityScript and Visual Studio can be used to code for unity in C#. Additionally, learning C# allows using it outside of Unity as well unlike UnityScript.

Pro Understanding of basics
Because of the verbosity and easy syntax, Pascal language is relatively easier to be learned and understood, even for someone who has no programming knowledge. It's said that Pascal code —if written well— is like reading pseudo code.

Pro Easy
Pascal / Object pascal was used in schools during the 2000's to teach kids the basics of object oriented programming.
Pro Clear syntax
Pascal's syntax is clear and concise, for example:
procedure test();
begin
DoSomething();
end;
Pro Enforces good programming practice
Numerous strong compile time checks with optional runtime checks ensure one doesn't do stupid things and even when one does (because the compiler can't prove it at compile time), the binary will check and report it at runtime.
Correct modular programming implementation with proper namespacing, no file inclusion hack.
Pro Cross platform
Pascal development tools are available almost on every available platform, especially using Free Pascal. Pascal language is available on desktop like Mac, BSD, Linux, Windows, Solaris, etc.; on mobile like iOS, Android, etc.; also on managed environments like Java Virtual Machine (JVM) and .Net/Mono framework . There are even some Pascal to JavaScript transpilers such as Smart Pascal, so you can write client side web app using Pascal as well, if you really want to.

Pro Tons of academic reading
Being known as the programming language for education, especially in the 90's, there many academic reading and tutorials available on the internet.
Pro Fast compilation
The compiler is fast, really fast. Compared to C/C++, the delphi compiler is designed to compile a decent sized desktop application in seconds rather than minutes.

Pro Flexible
Using the Free Pascal Compiler (the main Pascal distribution) you can code in a language that can be procedural and imperative now, but it can became object-oriented simply adding a directive at the start of the source
Pro Easy GUI creation
Visual Basic may have predated Delphi but Delphi was the ground breaking visual designer which set the standards expected today by most GUI developers. Its rich component set was well designed, structured and extensible, it even has the ability to display live data from the attached database in its data controls.
Pro Assembler Code and DLL/SO creation
You can put Assembler code in Intel or AT&T formats, to achieve great results of speed and accuracy. It is possible to create Dynamic Link Libraries or their equivalent in Unix-like systems so it's relatively easy to use and powerful.
Pro Rich existing libraries
Both shipped with implementations and spread all over the web. Both natively written or bindings to libraries written in other languages. Typically to build non-trivial applications there's no need to surf the web as many things are implemented already. Streaming, output templating, socket & networking, web, database, image manipulation, high performance graphics, (de)compression, (de|en)cryption, regex, unit testing, json manipulation, google API, indexing, multithreading, external process management, the list just goes on and on!
Pro Still active
From the early roots of Pascal, Delphi has been developed and is still actively supported. It is used in many desktop applications today, and even supports multi platform coding.
Pro Suitably close to modern languages, without the pitfalls
It was developed as a teaching language and it shows. No syntax pitfalls and gently encourages good style.
Pro Extensive third party libraries
There are large collections of third party components, many free which enable developers to add wide ranging and complex functionality to their code with ease
Pro Component based (reusability, decoupled, rich design architecture)
Pro Reliable language and code base
Most code from the Turbo Pascal days in the 80s still compiles, yet the language has since been adapted and extended with modern concepts, introducing OOP and interfaces, exception handling, native Unicode support, anonymous methods, generics, ARC and more.
Pro Available on a ridiculous number of platforms
FreePascal is available on/for Intel x86 (including 8086), AMD64/x86-64, PowerPC, PowerPC64, SPARC, ARM, AArch64, MIPS and the JVM. Supported operating systems include Linux, FreeBSD, Haiku, Mac OS X/iOS/iPhoneSimulator/Darwin, DOS (16 and 32 bit), Win32, Win64, WinCE, OS/2, MorphOS, Nintendo GBA, Nintendo DS, Nintendo Wii, Android, AIX and AROS.
Pro Language depth
Object Pascal is being used to write custom kernels (Ultibo) and operating-systems for various ARM boards. So the way you work with the code scales from low-level to pure OOP high-level. Object Pascal has the same level of depth that you find in C/C++ but with added productivity.
Pro Incredible GUI design tools
Lazarus and Delphi are both incredible GUI design tools, making rapid development a reality.
Making changes to a GUI doesn't mean switching tools or waiting for things to load, it's right there as part of your core tools.
Pro Dynamic evolution of language
Object Pascal language still evolving and being updated by Delphi (Embarcadero) and Free Pascal team (Lazarus).
Pro Well balanced for desktop development
For desktop development, Delphi is productive, the code is easy to understand, compilation speed is blazing, and it produces well performing applications that are easy to deploy. The perfect balance between C# and C++.
Pro Fast execution
The compiler generates fast and optimized code. No stop-the-universe garbage collection.
Pro Automatic memory management
The new Delphi compilers are powered by Automatic Reference Counting to ease development.
Pro Excellent database development
Cons

Con Older versions lacks standard-library support for immutable data structures

Con Complex syntax
Too many syntactic constructs to learn before it becomes usable.
Con .NET is a mess
Continual drama with standards, updates, Microsoft, and being really cross-platform.
Con Excessively class based OOP oriented
Limits users into overly using awkward paradigm and creating another kind of spaghetti code.
Con A pale imitation of Java
C# is a Java-like language, but Microsoft failed to imitate Java's consistency. For instance, C# has types that cannot be passed by address (e.g. DateTime), forcing the developer to use ugly workarounds.
Con Too easy to write multithreading apps that are buggy
Many web frameworks or GUI libraries will push novice users to writing multithreaded code, which leads to frustrating race condition bugs.
Other languages with multithreading push users towards safe constructs, like passing messages and immutable or synchronized containers. But in C# the data structures aren't synchronized by default, and it's too easy to just set a field and observe the result from another thread (until you compile with Release, and now you have a heisenbug).
Con Often-used products in most C# development environments get expensive
The majority of the C# development community uses Microsoft products which are not all free and open-source. As you get into the enterprise level of some of these products and subscriptions, the expense is multiple factors of 10 greater.
While you can use a fully open-source and free C# environment, the community around that is much smaller. While this can be said for other languages as well, the majority of C# falls into the for-pay Microsoft realm.
Con Popularly used on Visual Studio (proprietary)
Most people learn and depend on Visual Studio (proprietary) to write C#. The result is people learn how to use an IDE and not the concepts or fundamentals of good programming. However, you don't need VS to develop in C#, all you need is the dotnet CLI and a text editor that supports OmniSharp like VSCodium, Vim and Emacs.
Con Large Library and eco system makes it unsuitable for beginers
yes, all the information about the .net framework is in one place, but it is so extense that it introduces a steep learning curve for newcomers to the field of programming languages.

Con Niche language
Most use of this language will be found in jobs supporting legacy code. It will be hard to find things to do with this language outside of that niche.
Con No up-to-date version of language standards
In 1983, and update in 1990, the language was standardized with two standards: ISO/IEC 7185:1990 Pascal and ISO/IEC 10206:1990 Extended Pascal. However, Object Pascal extensions to the language have no official standards but in 1993, a draft proposal for object oriented Pascal standard was re; for review purposes only. There are no standards for modern features and enhancements, thus various Pascal dialects like Delphi or HP Pascal has their own enhancements and features.
Con Effectively obsolete
While this may have been an ok choice 25 years ago, it no longer is. Consider Python, Go or Clojure.
Con Unnecessary heavy syntax
Begin.. end. Pascal would have been great with curly braces.. but then again, that's what C is for. It's an academic language which was used in the past, but not much anymore today.
Con All variables, types, constants and functions must be declared at the beginning of the code
