doc: fix typo in documentation

Documentation/op-guide/gateway.md

@@ -4,7 +4,7 @@
 
 etcd gateway is a simple TCP proxy that forwards network data to the etcd cluster. The gateway is stateless and transparent; it neither inspects client requests nor interferes with cluster responses.
 
-The gateway supports multiple etcd server endpoints and works on a simple round-robin policy. It only routes to available enpoints and hides failures from its clients. Other retry policies, such as weighted round-robin, may be supported in the future.
+The gateway supports multiple etcd server endpoints and works on a simple round-robin policy. It only routes to available endpoints and hides failures from its clients. Other retry policies, such as weighted round-robin, may be supported in the future.
 
 ## When to use etcd gateway
 

Documentation/op-guide/grpc_proxy.md

@@ -194,7 +194,7 @@ $ ETCDCTL_API=3 etcdctl --endpoints=localhost:2379 get my-prefix/my-key
 
 ## TLS termination
 
-Terminate TLS from a secure etcd cluster with the grpc proxy by serving an unencrypted local endpoint.
+Terminate TLS from a secure etcd cluster with the gRPC proxy by serving an unencrypted local endpoint.
 
 To try it out, start a single member etcd cluster with client https:
 
@@ -211,7 +211,7 @@ $ ETCDCTL_API=3 etcdctl --endpoints=http://localhost:2379 endpoint status
 $ ETCDCTL_API=3 etcdctl --endpoints=https://localhost:2379 --cert=client.crt --key=client.key --cacert=ca.crt endpoint status
 ```
 
-Next, start a grpc proxy on `localhost:12379` by connecting to the etcd endpoint `https://localhost:2379` using the client certificates:
+Next, start a gRPC proxy on `localhost:12379` by connecting to the etcd endpoint `https://localhost:2379` using the client certificates:
 
 ```sh
 $ etcd grpc-proxy start --endpoints=https://localhost:2379 --listen-addr localhost:12379 --cert client.crt --key client.key --cacert=ca.crt --insecure-skip-tls-verify &

Documentation/op-guide/maintenance.md

@@ -66,7 +66,7 @@ When `--auto-compaction-retention=10h`, etcd first waits 10-hour for the first c
 
 Whether compaction succeeds or not, this process repeats for every 1/10 of given compaction period. If compaction succeeds, it just removes compacted revision from historical revision records.
 
-In [v3.3.3](https://github.com/etcd-io/etcd/blob/master/CHANGELOG-3.3.md), `--auto-compaction-mode=revision --auto-compaction-retention=1000` automatically `Compact` on `"latest revision" - 1000` every 5-minute (when latest revision is 30000, compact on revision 29000). Previously, `--auto-compaction-mode=periodic --auto-compaction-retention=72h` automatically `Compact` with 72-hour retention windown for every 7.2-hour.  **Now, `Compact` happens, for every 1-hour but still with 72-hour retention window.** Previously, `--auto-compaction-mode=periodic --auto-compaction-retention=30m` automatically `Compact` with 30-minute retention windown for every 3-minute. **Now, `Compact` happens, for every 30-minute but still with 30-minute retention window.** Periodic compactor keeps recording latest revisions for every compaction period when given period is less than 1-hour, or for every 1-hour when given compaction period is greater than 1-hour (e.g. 1-hour when `--auto-compaction-mode=periodic --auto-compaction-retention=24h`). For every compaction period or 1-hour, compactor uses the last revision that was fetched before compaction period, to discard historical data. The retention window of compaction period moves for every given compaction period or hour. For instance, when hourly writes are 100 and `--auto-compaction-mode=periodic --auto-compaction-retention=24h`, `v3.2.x`, `v3.3.0`, `v3.3.1`, and `v3.3.2` compact revision 2400, 2640, and 2880 for every 2.4-hour, while `v3.3.3` *or later* compacts revision 2400, 2500, 2600 for every 1-hour. Futhermore, when `--auto-compaction-mode=periodic --auto-compaction-retention=30m` and writes per minute are about 1000, `v3.3.0`, `v3.3.1`, and `v3.3.2` compact revision 30000, 33000, and 36000, for every 3-minute, while `v3.3.3` *or later* compacts revision 30000, 60000, and 90000, for every 30-minute.
+In [v3.3.3](https://github.com/etcd-io/etcd/blob/master/CHANGELOG-3.3.md), `--auto-compaction-mode=revision --auto-compaction-retention=1000` automatically `Compact` on `"latest revision" - 1000` every 5-minute (when latest revision is 30000, compact on revision 29000). Previously, `--auto-compaction-mode=periodic --auto-compaction-retention=72h` automatically `Compact` with 72-hour retention windown for every 7.2-hour.  **Now, `Compact` happens, for every 1-hour but still with 72-hour retention window.** Previously, `--auto-compaction-mode=periodic --auto-compaction-retention=30m` automatically `Compact` with 30-minute retention windown for every 3-minute. **Now, `Compact` happens, for every 30-minute but still with 30-minute retention window.** Periodic compactor keeps recording latest revisions for every compaction period when given period is less than 1-hour, or for every 1-hour when given compaction period is greater than 1-hour (e.g. 1-hour when `--auto-compaction-mode=periodic --auto-compaction-retention=24h`). For every compaction period or 1-hour, compactor uses the last revision that was fetched before compaction period, to discard historical data. The retention window of compaction period moves for every given compaction period or hour. For instance, when hourly writes are 100 and `--auto-compaction-mode=periodic --auto-compaction-retention=24h`, `v3.2.x`, `v3.3.0`, `v3.3.1`, and `v3.3.2` compact revision 2400, 2640, and 2880 for every 2.4-hour, while `v3.3.3` *or later* compacts revision 2400, 2500, 2600 for every 1-hour. Furthermore, when `--auto-compaction-mode=periodic --auto-compaction-retention=30m` and writes per minute are about 1000, `v3.3.0`, `v3.3.1`, and `v3.3.2` compact revision 30000, 33000, and 36000, for every 3-minute, while `v3.3.3` *or later* compacts revision 30000, 60000, and 90000, for every 30-minute.
 
 ## Defragmentation