DOCS-914 copy edits in the indexes.txt

Author: kay-kim

source/applications/indexes.txt

@@ -32,8 +32,8 @@ of index configurations with data sets similar to the ones you'll be
 running in production to see which configurations perform best.
 
 MongoDB can only use *one* index to support any given
-operation. However, each clause of an :operator:`$or` query can use
-its own index.
+operation. However, each clause of an :operator:`$or` query may use
+a different index.
 
 .. _indexes-create-to-match-queries:
 
@@ -63,7 +63,7 @@ you also can query on ``category`` combined with ``item``.
 (To query on multiple keys and sort the results, see :ref:`index-sort`.)
 
 With the exception of queries that use the :operator:`$or` operator, a
-query cannot use multiple indexes. A query must use only one index.
+query does not use multiple indexes. A query uses only one index.
 
 .. _compound-key-indexes:
 .. _indexes-compound-key-indexes:
@@ -207,7 +207,7 @@ are equality matches.
 Ensure Indexes Fit RAM
 ----------------------
 
-For fastest processing, ensure that your indexes fit entirely in RAM so
+For the fastest processing, ensure that your indexes fit entirely in RAM so
 that the system can avoid reading the index from disk.
 
 To check the size of your indexes, use the
@@ -226,10 +226,10 @@ available but also must have RAM available for the rest of the
 
 If you have and use multiple collections, you must consider the size
 of all indexes on all collections. The indexes and the working set must be able to
-fit in RAM at the same time.
+fit in memory at the same time.
 
 There are some limited cases where indexes do not need
-to fit in RAM. See :ref:`indexing-right-handed`.
+to fit in memory. See :ref:`indexing-right-handed`.
 
 .. seealso:: For additional :doc:`collection statistics
    </reference/collection-statistics>`, use :dbcommand:`collStats` or
@@ -241,7 +241,7 @@ Indexes that Hold Only Recent Values in RAM
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Indexes do not have to fit *entirely* into RAM in all cases. If the
-value of the indexed field grows with every insert, and most queries
+value of the indexed field increments with every insert, and most queries
 select recently added documents; then MongoDB only needs to keep the
 parts of the index that hold the most recent or "right-most" values in
 RAM. This allows for efficient index use for read and write

source/reference/operator/explain.txt

@@ -9,7 +9,7 @@ $explain
 
 .. operator:: $explain
 
-   :operator:`$explain` operator provides information on the query
+   The :operator:`$explain` operator provides information on the query
    plan. It returns a :doc:`document </reference/explain>` that describes
    the process and indexes used to return the query. This may provide
    useful insight when attempting to optimize a query.