What is the difference between zabbix agent VS zabbix agent 2

 Difference between zabbix agent VS zabbix agent 2

This blog describes the differences between the Zabbix agent and the Zabbix agent 2:

Parameter	Zabbix agent	Zabbix agent 2
Programming language	C	Go with some parts in C
Daemonization	yes	by systemd only (yes on Windows)
Supported extensions	Custom loadable modules in C.	Custom plugins in Go.
Supported platforms	Linux, IBM AIX, FreeBSD, NetBSD, OpenBSD, HP-UX, Mac OS X, Solaris: 9, 10, 11, Windows: all desktop and server versions since XP	Linux, Windows: all desktop and server versions since XP.
Supported crypto libraries	GnuTLS 3.1.18 and newer OpenSSL 1.0.1, 1.0.2, 1.1.0, 1.1.1 LibreSSL – tested with versions 2.7.4, 2.8.2 (certain limitations apply, see the Encryption page for details).	Linux: OpenSSL 1.0.1 and later is supported since Zabbix 4.4.8. MS Windows: OpenSSL 1.1.1 or later. The OpenSSL library must have PSK support enabled. LibreSSL is not supported.
Processes	A separate active check process for each server/proxy record.	Single process with automatically created threads. The maximum number of threads is determined by the GOMAXPROCS environment variable.
Metrics	UNIX: see a list of supported items. Windows: see a list of additional Windows-specific items.	UNIX: All metrics supported by Zabbix agent. Additionally, the agent 2 provides Zabbix-native monitoring solution for: Docker, Memcached, MySQL, PostgreSQL, Redis, systemd, and other monitoring targets

Concurrency	Active checks for single server are executed sequentially.	Checks from different plugins or multiple checks within one plugin can be executed concurrently.
Scheduled/flexible intervals	Supported for passive checks only.	Supported for passive and active checks.
Third party traps	no	yes

Persistent storage	no	yes
Persistent files for log*[] metrics	yes (only on Unix)	no
Timeout settings	Defined on an agent level only.	Plugin timeout can override the timeout defined on an agent level.
Changes user at runtime	yes (Unix-like systems only)	no (controlled by systemd)
User-configurable ciphersuites	yes	no