The Unix philosophy is
Write programs that do one thing and do it well.
Write programs to work together.
Write programs to handle text streams, because that is a universal interface.
Many of these unix programs would later end up as wildly successful web companies. (This original observation comes from Chris Dixon back in 2014).
grep (Google) The grep utility searches any given input files, selecting lines that match one or more patterns.
man (StackOverflow) Displays and formats manual pages for different unix commands.
cron (Zapier) Executes other unix commands or scripts on a schedule.
rsync (Dropbox) Quickly syncs files or folders to a remote server.
curl (Postman) Transfer data to a server over different protocols (HTTP, etc.)
top|ps (Datadog) Display information about currently running processes.
ssh -L (Tailscale, Zerotier) Connects to a remote server over the SSH protocol. The
-L command creates an SSH tunnel through a server (usually called a "jumpbox"). Modern VPNs make it (arguably) easier to replicate this functionality.
Not quite "Unix philosophy" programs, but other command line programs that found their way to the web.
irc (Slack, Discord) A terminal user interface to the Internet Relay Chat Protocol. Create and chat in channels, choose nicknames, issue slash commands.
vi|vim|emacs (VSCode) Lightweight text editor with a command palette and extensive plugin system.
lynx (Netscape, Chrome, Safari, etc.) A text-based web browser to use inside a terminal. Lynx was originally released in 1992, right around the same time as Mosaic was developed by Marc Andreessen.