What is the difference between Web WeChat and WeChat for Windows?

Web WeChat and WeChat for Windows are both designed to provide users with a convenient chatting platform to allow quick and convenient file transfers between mobile and PC.

They differ in the following aspects:

1- Web WeChat can be logged in to at http://web.wechat.com; It uses browser-based login method.

2- WeChat for Windows must be downloaded and installed on PC before using. It uses client-based login mode.

3- WeChat for Windows allows users to backup and restore their chat history, while Web WeChat currently doesn’t offer a backup and restore feature

Source: WeChat Help Center