Ping
Ping shows whether a host answers and how long a round trip takes on one path at one moment.
Definitions only — a term explained here is not a service we sell.
Ping sends ICMP echo requests and times the replies, so it proves reachability and round-trip time for that path at that moment. It says nothing about bandwidth, the application or the full path.
What ping measures and misses
Ping is a network-layer test. It does not open a TCP port, resolve a name, complete a TLS handshake or ask an application to do work. A fast ping does not mean a fast API, because DNS, connection setup, TLS and server processing can dominate the wait.
ICMP is often rate-limited, deprioritised or blocked. A timeout can mean a firewall policy rather than a dead host. Record the vantage point, because a ping from an office and one from a mobile network measure different paths. The Ping tool reports round trip and loss for the target you choose.