[nginx] README: add details about stable and master branches

[noreply at nginx.com]

details:   https://github.com/nginx/nginx/commit/0daee9a4806595bfae752a5b09a0bcc2c5e7af30
branches:  master
commit:    0daee9a4806595bfae752a5b09a0bcc2c5e7af30
user:      Michael Vernik <m.vernik at f5.com>
date:      Mon, 9 Sep 2024 23:53:39 -0700
description:
README: add details about stable and master branches


---
 README.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/README.md b/README.md
index c6c18f56c..20003e99f 100644
--- a/README.md
+++ b/README.md
@@ -75,6 +75,9 @@ Follow these steps to download and install precompiled NGINX binaries. You may a
 ## Stable and Mainline binaries
 NGINX binaries are built and distributed in two versions: stable and mainline. You'll need to [decide which is appropriate for your purposes](https://docs.nginx.com/nginx/admin-guide/installing-nginx/installing-nginx-open-source/#choosing-between-a-stable-or-a-mainline-version).
 
+> [!TIP]
+> Stable binaries are built from the various stable branches and mainline binaries are built from the [master](https://github.com/nginx/nginx/tree/master) branch maintained in this repository.
+
 ## Linux binary installation process
 The NGINX binary installation process takes advantage of package managers native to specific Linux distributions. For this reason, first-time installations involve adding the official NGINX package repository to your system's package manager.