Do you see boxes and or strange circles in the Hebrew text? This web site uses Hebrew vowels and accents. In order for you to view them properly, you need a unicode Hebrew font with the vowels and accents. I highly recommend the Ezra SIL font, but you may also use the SBL Hebrew font.
Download one, install it, then come back.
Greek
For nice looking Greek text, download and install the Gentium font:
מִזְמ֥וֹר לְדָוִ֑ד יְהוָ֥ה רֹ֝עִ֗י לֹ֣א אֶחְסָֽר׃
מִזְמוֹר—is from an old Akkadian word zimru meaning the melody or sound made by an instrument. Most Semitic languages have cognates of this word. A mizmor is the technical term for a psalm, but can also generally mean a song sung to an instrumental accompaniment. The word psalm itself comes from the Greek word ψαλμοί psalmoi, which has the meaning of "a song accompanied by a stringed instrument." The Greek letter ψ or psi, which is first letter of psalmoi is often used in scholarly works as an abbreviation for the Book of Psalms. The Hebrew title of the Book of Psalms is תהליםtehillim, "praises," from the root הלל, "to praise" (as in hallelujah).
אֶחְסָר—Qal, imperfect, 1st person singular. חסר—to decrease or lesson, to lack, to be without
Atnach אַתְנָח—marks the last word in the first half of the verse. In general it can be viewed as the main pause in the verse. The atnach looks like an upside down V or the caret mark '^'. It is under the word לְדָוִ֑ד
Munach מוּנָח—a conjunctive accent which indicates that the word it is placed under is connected to the following word. The munach looks like a carpenter's square, or a right angle. It is under the lo in לֹ֣א אֶחְסָֽר, which of course ties lo with 'echsar.
Silluq סִלּוּק—marks the last word in the verse. It is a short vertical line. It is under the last word in this verse, אֶחְסָֽר.