fix typo
as --> and
diff --git a/doc/specs/thrift-binary-protocol.md b/doc/specs/thrift-binary-protocol.md
index af4bd81..e751a02 100644
--- a/doc/specs/thrift-binary-protocol.md
+++ b/doc/specs/thrift-binary-protocol.md
@@ -80,7 +80,7 @@
### Double encoding
Values of type `double` are first converted to an int64 according to the IEEE 754 floating-point "double format" bit
-layout. Most run-times provide a library to make this conversion. Both the binary protocol as the compact protocol then
+layout. Most run-times provide a library to make this conversion. Both the binary protocol and the compact protocol then
encode the int64 in 8 bytes in big endian order.
### Boolean encoding