Typescript is a Javascript-based open-source project to develop type systems that are designed for more manageable type checking that semantically match JavaScript's. This offers an intuitive and subtle interface for advanced programmers. It is a "type" system that also makes programming easier. It adds new type to the JavaScript language like number, string, etc.

Typescript is a better way to write JavaScript. It offers more alerts for errors and will save you time by not having to repeat the same work. Typescript should be used so that you will know if something is mismatched or not.

TypeScript can catch errors like typos and logic errors and more. TypeScript can also power editor tooling like accurate code completion or navigating to the right part of your program.

Microsoft announced Typescript 4.4 Release in their blog.

To get started using TypeScript 4.4, you can get it through NuGet, or use npm with the following command:

npm install typescript

TypeScript 4.4 offers several notable improvements including:

• Control Flow Analysis of Aliased Conditions and Discriminants
• Symbol and Template String Pattern Index Signatures
• Defaulting to the unknown Type in Catch Variables (--useUnknownInCatchVariables)
• Exact Optional Property Types (--exactOptionalPropertyTypes)
• Class static Blocks
• tsc --help Updates and Improvements
• Performance Improvements
• Spelling Suggestions for JavaScript
• Inlay Hints
• Breaking Changes

To know more about the above improvements check the Microsoft Blog - Link