Kinds of proxy service run on Linux systems.

There are many kinds of proxy servers for Linux systems, each with their own specific features.

Some known proxy server software and config to setup:

1. Squid: A high-performance proxy server that can be used for caching, filtering, and authentication.
   [ http://www.squid-cache.org ]
   Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more.
2. Apache: A web server that can also act as a proxy server, allowing users to access content from other web servers.
   [ https://httpd.apache.org/docs/2.4/mod/mod_proxy.html ]
   Apache HTTP Server can be configured in both a forward and reverse proxy (also known as gateway) mode.
3. Nginx: A web server and reverse proxy server that is known for its high performance and scalability.
   [ https://docs.nginx.com/nginx/admin-guide/web-server/reverse-proxy ]
   NGINX Reverse Proxy
   Configure NGINX as a reverse proxy for HTTP and other protocols, with support for modifying request headers and fine-tuned bugffering of responses.
4. HAProxy: A high-availability proxy server that is often used for load balancing and failover.
   [ https://www.haproxy.org ]
   HAProxy is a free, very fast and reliable reverse-proxy offering high availability, load balancing, and proxying for TCP and HTTP-based applications. It is particularly suited for very high traffic web sites and powers a significant portion of the world's most visited ones.
5. Privoxy: A non-caching, privacy-enhancing web proxy that can be used for filtering and blocking unwanted content.
   [ https://www.privoxy.org ]
   Privoxy is a non-caching web proxy with advanced filtering capabilities for enhancing privacy, modifying web page data and HTTP headers, controlling access, and removing ads and other obnoxious Internet junk.
6. SOCKS proxy: A general purpose proxying protocol that routes network packets between a client and server through a proxy server.
   [ https://linuxcli.in/p/ssh-socks-proxy ]
   SOCKS proxy via SSh allows you to securely route your internet traffic through a remote server using the SSh protocol.

Each of these proxy servers has its own unique features, and it depend on the requirements.