Understanding the Differences Between HTTP GET and POST Methods

After learning about computers, the author clarifies common misconceptions about HTTP GET and POST methods.

GET and POST are the two basic HTTP request methods; the main visual difference is that GET places parameters in the URL while POST sends them in the request body.

Common interview “standard answers” list many differences, such as bookmarkability, caching, length limits, safety, etc.

GET is harmless on browser back, POST may resubmit.

GET URLs can be bookmarked; POST cannot.

GET can be cached automatically; POST is not cached unless configured.

GET supports only URL‑encoded data; POST supports multiple encodings.

GET parameters remain in browser history; POST parameters do not.

GET URL length is limited (≈2 KB in browsers, ≈64 KB on servers); POST has no such limit.

GET accepts only ASCII characters; POST has no character restriction.

GET exposes parameters in the URL, making it less secure for sensitive data.

GET sends parameters via URL; POST sends them in the request body.

The underlying transport for both methods is TCP/IP, so technically they are equivalent; the differences arise from HTTP specifications and practical limits imposed by browsers and servers.

In practice, a GET request usually involves a single TCP packet exchange (header + data), while a POST often requires two exchanges (header, 100‑Continue, then data), which can affect performance but also provides semantic clarity.

Therefore, when interviewers ask about GET vs POST, the answer should acknowledge both the protocol‑level equivalence and the real‑world constraints that make the two methods behave differently.