SOQL- (Salesforce Object Query Language) SOSL (Salesforce object Search Language)
Using SOQL we can Search only on one object one time. Using SOSL we can search on many objects at one time.
We can query on all fields of any datatype We can query only on fields whose data type is text,phone and Email.
We can use SOQL in the Triggers and the classes. We cannot use in Triggers but can in classes.
We can perform DML operation on sql query results. We cannot perform DML operation on search results.