Proxy - this is a computer or server that serves as an intermediate link in the chain of data exchange between the user(client) - the final Internet resource.
Most users (users) use a proxy to change their IP.

Some of the features of proxies:
Ensure that computers on the local network have access to the Internet.
Compress the data;
Cache data;
Restricting access from the local network to the external network.
Anonymity when entering and viewing various Internet resources (see proxy anonymity).
To overcome the limitations of resource availability in your country.

HTTP proxy - this type is the most popular. It is used for various tasks, among which the main one is to organize the work of browsers.
Frequent ports: 80, 8080, 3128.

Advantages:
Caching of downloaded files (pictures, pages) to increase speed of opening websites;
Connection speed limit;
Disadvantages:
Logs are being recorded;
View user traffic;
You cannot load a page that uses ssl (you cannot open a page that starts with https);

The same HTTP, just with the ability to protect personal information during transmission by using ssl.
How is that possible? HTTPS just encrypts the traffic using the algorithm that is resistant to hacking.
Frequent ports: 80, 8080, 3128.

Advantages:
Caches visited pages, thus speeding up their loading;
Has support for secure SSL connection;
It is impossible to track the transmitted data when working with it;
With all the advantages, it can transmit the real IP of the user.

Socks can reliably protect your personal information(traffic). Stable and common versions of the Protocol - SOCKS4 and proxy Socks5, have certain differences.
The difference lies in the fact that socks5 is integrated mechanisms to support a variety of authentication methods.
Socks5 supports UPD.
Frequent ports: 1080, 1081.

Advantages:
The real user IP is not passed in the query;
A large number of protocols are supported;
Has support for secure SSL connection;
Mail Protocol support;
Completely anonymous Protocol;
Have only elite type of anonymity;


Compared to HTTP and HTTPS - SOCKS proxies live longer, their speed is higher and anonymity is better.

A standard proxy server that leaves user data intact, that is, as it is.
Indicates that a proxy server is being used.
Displays the current IP of the user.

The following information is sent to the client server:
REMOTE_ADDR = IP proxy
HTTP_VIA = IP or proxy address (if proxy is used)
HTTP_X_FORWARDED_FOR = Your real IP

Do not give real anonymity.
Show that the proxy server is used, but does not give out the real IP of the user.

The following information is sent to the client server:
REMOTE_ADDR = IP proxy
HTTP_VIA = proxy (if proxy is used)
HTTP_X_FORWARDED_FOR = Proxy IP or a random address

Provide complete anonymity.
Do not give out the real IP of the user.
Does not show that the proxy is used.

The following information is sent to the client server:
REMOTE_ADDR = IP proxy
HTTP_VIA = blank
HTTP_X_FORWARDED_FOR = blank

If the variable has _X_ – this indicates that this variable is optional to use.