[mcepl]

Yes, a lot. All those zillion shell scripts which run the IT these days use it whenever they need to get to the Internet (surprisingly, it is much more common than wget(1), which in fact does more or less the same).

And, of course, everybody and their dog uses libcurl, directly or through some bindings to their programming language.

[chasil]

Curl actually does far more than wget.

Wget implements these protocols:

  $ man wget | fgrep 'HTTP, HTTPS, and FTP'
       the Web.  It supports HTTP, HTTPS, and FTP protocols, as well as

A full-featured curl (and specifically not the one distributed by Microsoft) implements additional protocols:

  C:\>curl --version
  curl 8.2.1 (x86_64-w64-mingw32) libcurl/8.2.1 OpenSSL/3.1.2 (Schannel) zlib/1.2.13 brotli/1.0.9 zstd/1.5.5 WinIDN libssh2/1.11.0 nghttp2/1.55.1 ngtcp2/0.18.0 nghttp3/0.14.0 libgsasl/2.2.0
  Release-Date: 2023-07-26
  Protocols: dict file ftp ftps gopher gophers http https imap imaps ldap ldaps mqtt pop3 pop3s rtsp scp sftp smb smbs smtp smtps telnet tftp ws wss
  Features: alt-svc AsynchDNS brotli gsasl HSTS HTTP2 HTTP3 HTTPS-proxy IDN IPv6 Kerberos Largefile libz MultiSSL NTLM SPNEGO SSL SSPI threadsafe UnixSockets zstd

Some of the particular protocols are limited - SMB, for example, is only SMBv1 (and not v2 or v3).

Microsoft's version is currently:

  C:\>curl --version
  curl 8.0.1 (Windows) libcurl/8.0.1 Schannel WinIDN
  Release-Date: 2023-03-20
  Protocols: dict file ftp ftps http https imap imaps pop3 pop3s smtp smtps telnet tftp
  Features: AsynchDNS HSTS HTTPS-proxy IDN IPv6 Kerberos Largefile NTLM SPNEGO SSL SSPI threadsafe Unicode UnixSockets